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The Origin, Distribution & Detection of Life in the Universe
2 – 4 September 2015, Centre for Planetary Sciences at UCL/Birkbeck
Programme and Abstracts
ASB6: Darwin front entrance Directions to the Darwin Building
Between certain hours (arrivals from 9-10am, around lunchtime 1-2.30pm and close of day from 5/5.30pm)
the Darwin Building will be accessible from the front Gower Street entrance.
At all other times please enter the Darwin Building from the rear entrance via Darwin Walk (circled
above), off of Malet Place and follow the signs. Malet Place runs parallel with Gower Street and can be
accessed directly from Torrington Place.
1 | WELCOME AND INFORMATION | ASB6
Welcome
Welcome to the sixth biennial conference of the Astrobiology Society of Britain – ASB6:
The Origin, Distribution & Detection of Life in the Universe – hosted by the Centre for
Planetary Sciences at UCL/Birkbeck, and located at University College London.
Astrobiology is a multidisciplinary topic that brings together many branches of science,
including astronomy, astrochemistry, astrobiology technology, biology, chemistry of life,
development of life-forms in other environments, exoplanets, extremophiles,
geomicrobiology, habitable zones, humans in space, life’s origins, Mars, meteorites, microbial
communities, origin of complex organics, panspermia, planetary protection, prebiotic
climates, public engagement, SETI. ASB6 will address these topics and more.
As well as the stimulating scientific programme, we look forward to seeing you after the
talks on Wednesday for the Evening Reception. On Thursday 3 September there will be a
public talk by Prof. Lynn Rothschild (NASA Ames) on The Search for Life in the Universe,
which we encourage you to attend. After the talk, there will be a swift exodus to the
Spaghetti House restaurant nearby for the conference dinner. In addition, the Astrobiology
Society of Britain will chair a special community session to close the conference on Friday,
entitled “Astrobiology and the Community. An Open Discussion”.
We hope you enjoy ASB6 and that this forum will foster the exchange of ideas with your
colleagues, such that it is a productive three days for all.
Wishing you an enjoyable stay in London,
Terry Kee, Ian Crawford and the ASB6 Local Organising Committee
Venue
UCL's main campus is situated in the heart of the Bloomsbury area of central London and
benefits from great transport links and easy access to most of the city's major attractions.
The main entrance to UCL is on Gower Street, London WC1E 6BT.
The ASB6 conference will be held in the Darwin lecture theatre and associated
classrooms, located in the basement of the Darwin Building.
UCL Darwin B40 lecture theatre: Oral presentations
UCL Darwin basement foyer: Registration, sponsor and publisher stands.
UCL Darwin B05 and B15 classrooms: Coffee breaks, posters, Wednesday evening
reception.
You can access various UCL maps online for detailed directions in the surrounding area:
https://www.ucl.ac.uk/maps.
2 | WELCOME AND INFORMATION | ASB6
Posters
Posters should be displayed in rooms B05 and B15 in the basement of the Darwin Building
for the duration of the conference.
Velcro stickers and drawing pins will be provided for fastening posters to the boards. There
is no fixed order assigned for the posters as numbers have been limited to 20, so please
choose where you wish to display your research.
The poster preview talks will take place on Wednesday 2 September at 16:45 in the
Darwin lecture theatre, prior to the evening reception. There will be 2 minutes per poster
and we recommend no more than two slides.
Coffee breaks and lunch
Free coffee breaks will be served on arrival, at mid-morning and mid-afternoon on all three
days of the conference. Lunch is not provided but participants are able to purchase meals in
the plentiful restaurants, cafes and pubs in the surrounding area of UCL.
Internet
Wireless internet access for ASB6 participants is available free of charge via the UCL Guest
network.
The Wi-Fi event code is “asb6-wifi” and the following steps give you a guideline on how to
access the network:
1. Connect to the UCLGuest Wireless Network.
2. Open a web browser and navigate to a page outside of UCL. The browser will
automatically redirect to the UCLGuest Welcome page.
3. Click on the link to the Self Service page; enter your information in the fields
provided.
4. Click Generate Account.
5. Your username and password will be displayed on the screen; these details will also
be sent to your e-mail address. Make a note of your username and password as you
will need them each time you log into UCLGuest (the system will not remember
your login details).
6. Click on the link to the Login page and enter your details.(Please be aware it may
take up 60 seconds for your account to become active after it’s been generated. If
you cannot log in please wait a short while and try again).
UCL also uses the Eduroam wireless network throughout the UCL Campus and at
participating Higher Education Institutions (HEIs). The service is also available in Halls of
Residence buildings.
3 | WELCOME AND INFORMATION | ASB6
Evening reception
We invite all conference participants to join us for the Evening Reception on Wednesday 2
September, from 17:30-19:30 in the Darwin breakout rooms B05 and B15.
Public talk
A public talk by Professor Lynn Rothschild (NASA Ames): "The Search for Life in the
Universe" will take place on Thursday 3 September at 18:00 in the Darwin lecture theatre.
ASB6 delegates are warmly encouraged to attend this free event, and do not have to
register. Attendance is open to all but registration for non-delegates is necessary (via the
Eventbrite page: https://www.eventbrite.com/e/asb6-public-talk-the-search-for-life-in-theuniverse-by-prof-rothschild-tickets-18001257245) as places are limited.
Conference dinner
The conference dinner will take place in the evening on Thursday 3 September from 19:30,
immediately after the Public Talk.
The dinner will be held at the Spaghetti House on Goodge Street, a short walk from UCL:
Address: 15 Goodge Street, London, W1T 2PQ
Telephone: 020 7636 6582
There will be a three-course set menu and some wine provided as part of your registration
fee if you selected the registration option that includes the conference dinner.
Unfortunately, we cannot accommodate last-minute additions to this event. On arrival at
the restaurant, please head up to the third floor and choose your place card from the table
by the entrance, which should also remind you of your menu choice. You are free to choose
where you sit.
ASB special session
The Astrobiology Society of Britain will chair a special community session to close the
conference on Friday 4 September at 16:10 in the Darwin lecture theatre, entitled
“Astrobiology and the Community. An Open Discussion”.
Local Organising Committee
Scientific Organising Committee
Ian Crawford (Chair)
Jo Fabbri (Administrator)
Louise Alexander
Eloi Camprubi
Pete Grindrod
Jennifer Harris
Barry Herschy
Elliot Sefton-Nash
Victor Sojo
Alexandra Whicher
Ian Crawford, Birkbeck (Chair)
Lewis Dartnell, University of Leicester (Vice Chair)
Nick Lane, University College London
Charles Cockell, University of Edinburgh
David Waltham, Royal Holloway
Zita Martins, Imperial College London
Manish Patel, Open University
Pete Grindrod, Birkbeck
Terry Kee, University of Leeds
4 | WELCOME AND INFORMATION | ASB6
Your hosts and sponsors
The Astrobiology Society of Britain is a learned society for people interested in the relationship
between life and its cosmic environment. This covers a vast diversity of topics and research
methodologies, encompassing observational astronomy, theoretical astrophysics, geological
expeditions and laboratory-based microbiology and prebiotic chemistry. For more information about
the ASB, please see our website: http://astrobiologysociety.org.
The Centre for Planetary Sciences at UCL/Birkbeck is one of the United Kingdom's leading centres
for planetary science. It houses expertise in understanding planets from their deep interiors, through
their surfaces and atmospheres, to their space environment. This expertise is complemented by
world leaders in astronomy, terrestrial and solar science, life and chemical sciences. For more
information about the CPS, please see our website: https://www.ucl.ac.uk/cps.
The UK Centre for Astrobiology is based at the University of Edinburgh. The Centre is affiliated to
the NASA Astrobiology Institute. The mission of the UK Centre for Astrobiology is to advance our
understanding of molecules and life in extreme environments on the Earth and beyond. It does this
with a combination of theoretical, laboratory, field and mission approaches. We apply this
knowledge to improving the quality of life on Earth and developing space exploration as two
mutually enhancing objectives. For more information about the UKCA, please see our website:
http://www.astrobiology.ac.uk.
The UK Space Agency is responsible for all strategic decisions on the UK civil space programme and
provides a clear, single voice for UK space ambitions. At the heart of UK efforts to explore and
benefit from space, we are responsible for ensuring that the UK retains and grows a strategic
capability in space-based systems, technologies, science and applications. We lead the UK’s civil
space programme in order to win sustainable economic growth, secure new scientific knowledge
and provide benefit to all citizens. The Agency provides funding for a range of programmes through
various routes including the Aurora Programme, National Space Technology Programme and FP7
and works closely with national and international academic, education and community partners. For
more information about the UKSA, please see our website:
https://www.gov.uk/government/organisations/uk-space-agency.
The Royal Astronomical Society, founded in 1820, encourages and promotes the study of
astronomy, solar-system science, geophysics and closely related branches of science. The Society
does this through organising scientific meetings, publishing international research and review
journals, recognising outstanding achievements by the award of medals and prizes, maintaining an
extensive library, supporting education through grants and outreach activities and representing UK
astronomy and geophysics nationally and internationally. For more information about the UKSA,
please see our website: https://www.ras.org.uk.
The organising committees for ASB6 are enormously grateful to both the Royal
Astronomical Society and the UK Space Agency for their generous support of this
conference.
5 | SCIENTIFIC PROGRAMME – WED 2 SEP | ASB6
Wednesday 2 September
09:30
10:00
Registration opens (will remain open all day)
Welcome
Ian Crawford
Session: Mars, Part 1, Chair: Ian Crawford
10:15
Sanjeev Gupta (invited)
Reconstructing ancient habitable environments in Gale crater
10:45
Elliot Sefton-Nash
ExoMars 2018 Rover Candidate Landing Sites: Aram Dorsum and
the Hypanis Vallis Delta
11:00
Robert Barnes
Using rover stereo-imagery to assess the habitability of ancient
aqueous environments on Mars
11:15
COFFEE
Session: Mars, Part 2, Chair: Charles Cockell
11:45
Claire Cousins (invited)
Using Earth-based analogues to further our exploration of Mars
12:15
Lewis Dartnell
Martian analogue samples and their spectroscopic biosignatures
12:30
Jacqueline Campbell
Detecting Polycyclic Aromatic Hydrocarbons on Mars
12:45
Kevin Devine
Analytical protocols for the extraction of aromatic carboxylic acids
from a Mars soil analogue, containing perchlorate salts
13:00
LUNCH
Session: Mars, Part 3, Chair: Manish Patel
14:00
Jane MacArthur
The alteration history of a Martian impact regolith NWA 811
14:15
Wren Montgomery
Organic records in impact excavated rocks on Mars
Session: Missions/Instruments, Chair: Manish Patel
14:30
Charlotte Blake-Kerry
UKSA briefing
14:45
Gerhard Kminek
(invited)
Planetary protection for life detection missions
15:15
Roy Adkin
Novel Fluorescent Sensors for the Detection of Organic Molecules
in Extra-Terrestrial Samples
15:30
David Cullen
CubeSat and CubeSat-like payloads for astrobiology, fundamental
biology and human cell biology studies
15:45
COFFEE
Session: Exoplanet special / Poster talks, Chair: Dave Waltham
16:15
16:45
17:30
Giovanna Tinetti
(invited)
Exoplanet special: Prospects to identify habitable environments in
our Galaxy through remote sensing spectroscopy
Poster Talks
RECEPTION
6 | SCIENTIFIC PROGRAMME – THU 3 SEP | ASB6
Thursday 3 September
09:00
ARRIVALS
Session: Cosmochemistry / Meteorites, Chair: Jane MacArthur
09:30
Serena Viti (invited)
Complex organic molecules in star forming regions
10:00
Hilary Downes
Early delivery of Carbon to the Earth under reducing conditions
10:15
Zita Martins
10:30
Torsten Henkel
10:45
Richard Matthewman
The amino acid and hydrocarbon contents of the Paris meteorite,
the most primitive CM chondrite
First in-situ analysis of amino acids in the Murchison meteorite with
C60-TOFSIMS
Irradiation of organic materials in the presence of lunar minerals: can
biomarkers from the early Earth survive on the Moon?
11:00
COFFEE
Session: Origins of life / Extremophiles / Early history of life, Part 1, Chair: Terry Kee
11:30
Nick Lane (invited)
Clues from bioenergetics to the origin of life
12:00
Victor Sojo
On the biogenic origins of homochirality
12:15
Alex Whicher
Acetyl phosphate as the first energy currency
12:30
David Bryant
Peptide and proto-cell formation driven by the same energy
currency system
12:45
Sohan Jeeta
Hypothesis: network of RNAs and their influence on life
13:00
LUNCH
Session: Origins of life / Extremophiles / Early history of life, Part 2, Chair: Claire Cousins
14:00
Lynn Rothschild (invited)
Synthetic astrobiology
14:30
Terry Kee
Electrochemical assaying of membrane-organic interactions.
Potential applications in astrobiology
14:45
Lotta Purkamo
Microbial community structure, activity and functionality from six
different depths of deep crystalline bedrock fracture zones from
Fennoscandian shield
15:00
John Allen
The evolutionary origin of oxygenic photosynthesis
15:15
Matthew Dodd
Primary vent structures and graphitic carbon in >3750Ma white
smoker type hydrothermal vent deposits
15:30
Dominic Papineau
A record of Precambrian hydrothermal vents?
15:45
COFFEE
Session: Exoplanets, Chair: Charles Cockell
16:15
Marcell Tessenyi
Twinkle - a UK mission to understand exoplanet atmospheres
16:30
William Bains
16:45
Jonti Horner
Biosignatures on super-earths with hydrogen-dominated
atmospheres
Dynamical constraints on multi-planet exoplanetary systems
17:00
Dave Waltham
Exomoons: How to find them and why they matter to Astrobiology
17:15
Jonti Horner
The structure of the ‘Asteroid-belt’ analogue around HR8799
17:30
Public lecture, Chair: Lewis Dartnell
18:00
Lynn Rothschild
19:30
BREAK
PUBLIC LECTURE: The search for life in the Universe
CONFERENCE DINNER
7 | SCIENTIFIC PROGRAMME – FRI 4 SEP | ASB6
Friday 4 September
09:00
ARRIVALS
Session: Habitability, Chair: Jonti Horner
09:30
Charles Cockell (invited)
Uninhabited habitats
10:00
Andrew Rushby
The carbonate-silicate cycle on habitable exoplanets: Implications for
long-term habitability
10:15
Indranil Banik
Snowball Earth & the struggle to maintain habitability: lessons for
exoplanets
10:30
Dave Waltham/Jonti
Horner
The Influence of Jupiter and Mars on Earth's orbital evolution
10:45
COFFEE
Session: ISS / HSF, Part 1, Chair: Zita Martins
11:15
Jean-Pierre de Vera
(invited)
The BIOMEX and BIOSIGN experiments on the ISS – two missions
in low Earth Orbit supporting future space missions for the search
for life on Mars and the icy moons
11:45
Charlotte Blake-Kerry
Principia, the International Space Station and the ELIPS programme
12:00
Mark Huckvale
Automatic Prediction of Fatigue from Speech Recordings
12:15
Nathaniel Szewczyk
NemaFlex: A microfluidic tool for phenotyping (neuro)muscular
strength in space-flown C. elegans
12:30
John Cain
The human exploration of space - confronting old and new chemical
risks to health
12:45
Timothy Etheridge
Establishing molecular mechanisms of and countermeasures to
muscle decline in space
13:00
LUNCH
Session: ISS / HSF, Part 2, Chair: Lewis Dartnell
14:00
Mark Burchell
Impact studies in the laboratory concerning survival of fossils
hypothetically launched toward the moon
14:15
Ian Crawford
The astrobiological case for human space exploration
Session: SETI, Chair: Lewis Dartnell
14:30
Alan Penny (invited)
The UK SETI Research Network
15:00
William Edmondson
What can we know about life on other worlds?
15:15
Lewis Pinault
Engaging a search for non-terrestrial artefacts on the moon
15:30
Mukesh Bhatt
Astrobiology and the legal definition of life
15:45
COFFEE
Community session, Chair: Terry Kee
16:10
ASB special session:
Astrobiology and the Community. An Open Discussion.
16:55
17:00
Ian Crawford
CLOSING REMARKS
CLOSE
8 | SCIENTIFIC PROGRAMME – POSTERS | ASB6
Posters
Connor Brolly
Are reduction spheroids signatures of microbial life?
Mark Fox-Powell
Ionic strength is a barrier to the habitability of Mars
John Holt
The Small Planetary Linear Impulse Tool, SPLIT, A New Approach to Rock
Sampling
Jonathan Horner
Astrobiology at the University of Southern Queensland
Jonathan Horner
The Instability of the 2:1 Mean Motion Resonance of Neptune
Jonathan Horner
2001 QR322 – an update on Neptune’s first unstable Trojan companion
Jonathan Horner
The Kilodegree Extremely Little Telescope (KELT): Searching for Transiting
Exoplanets in the Northern and Southern Sky
Jonathan Horner
BCool and the space weather of exoplanetary systems
Sohan Jheeta
Hypothesis: network of RNAs and their influence on life
Hanna Landenmark
An Estimate of the Total DNA in the Biosphere
Higor Mendonça De Jesus
Analysis of high throughput electrochemical detection of molecular signatures
based on membrane disruption behaviour
Michaela Musilova
Isolation of radiation resistant bacteria from Mars-analogue Antarctic Dry Valleys
by pre-selection
Philippe Nauny
Habitability and preservation of biomarkers in Martian analogues in Chile
Alex Price
Microbial community diversity in East Antarctic gypsum deposits
Lotta Purkamo
The DeepHotMicrobe Project - crowd funding as a tool for communicating
science and enhancing public engagement
Nick Thomas
Investigating preservation of molecular signatures of life in a unique Mars analogue
in the arid high-altitude Chilean Altiplano
Peter Woolman
Subsurface Halophiles: An Analogue for Potential Life on Mars
9 | ORAL ABSTRACTS – WED 2 SEP, MORNING – MARS | ASB6
ORAL ABSTRACTS
Reconstructing ancient habitable environments in Gale crater
Sanjeev Gupta (invited), Dave Rubin, Katie Stack, John Grotzinger, Rebecca Williams, Lauren
Edgar, Dawn Sumner, Ken Edgett, Melissa Rice, Aileen Yingst, Kevin Lewis, Michelle Minitti, Juergen
Schieber, Linda Kah, Ashwin Vasavada, Marie McBride. Mike Malin and the MSL Science Team
The search for sedimentary rocks with potential to contain evidence for past life on Mars is highly
dependent on reconstructing the palaeonevironmental context of sedimentary rock deposits and
identifying rocks that represent ancient habitable environments. NASA's Curiosity rover has been
exploring the sedimentary archive of Gale crater for 3 earth years and has uncovered a rich array of
clastic sedimentary rocks on her crossing of Aeolis Palus, the plains region between the Gale crater
rim and Aeolis Mons (Mount Sharp) to the basal sedimentary rocks of Mount Sharp.
The transition from Aolis Palus to the foothills rocks records a change from strata dominated by
coarse clastic deposits comprising sandstones and conglomerate facies to a succession at Pahrump
Hills that is dominantly fine-grained mudstones and siltstones with interstratified sandstone beds. In
this presentation we explore the sedimentary characteristics of the deposits, develop depositional
models in the light of observed physical characteristics and develop a working stratigraphic model to
explain geological relationships. Our observations suggest stratigraphic continuity between Aeolis
Palus and the Pahrump Hills succession that records a facies transition from fluvio-deltaic sediments
to facies deposited in a lacustrine succession.
10 | ORAL ABSTRACTS – WED 2 SEP, MORNING – MARS | ASB6
ExoMars 2018 rover candidate landing sites: Aram Dorsum and the Hypanis Vallis Delta
E. Sefton-Nash1, S. Gupta2, M. Balme3, P. Grindrod1, P. Fawdon3, J. Davis4 and the UK ExoMars
Landing Site Consortium.
(1) Dept. of Earth and Planetary Sciences, Birkbeck, University of London, UK, (2) Dept. of Earth Science & Engineering, Imperial College,
London, UK, (3) Dept. of Physical Sciences, The Open University, Milton Keynes, UK, (4) Dept. of Earth Sciences, UCL, UK.
The search for life on Mars is a cornerstone of international solar system exploration. The European
Space Agency is on schedule to launch the ExoMars Rover in 2018 to further this goal. The ExoMars
Rover’s key science objectives are to: 1) search for signs of past and present life on Mars; 2)
investigate the water/geochemical environment as a function of depth in the subsurface; and 3)
characterize the surface environment. ExoMars will drill down to 2 m to look for indicators of past
life using a variety of techniques, including assessment of morphology (potential fossil organisms),
mineralogy (past environments) and a search for organic molecules and their chirality (biomarkers).
The choice of landing site is vital if the objectives are to be met. The landing site must: (i) contain
material that is ancient in origin (≥3.6 Ga), but recent in surface exposure; (ii) show abundant
morphological and mineral evidence for long-term, or frequently recurring, aqueous activity; (iii)
global elevation
include numerous sedimentary outcrops that (iv) are distributedMarsover
the landing region (the typical
Rover traverse range is a few km, but the nominal size of landing ellipses is ~104 x 19 km). Various
engineering constraints also apply, including: (i) latitude limited to 5º S to 25º N; (ii) maximum
altitude of the landing site 2 km below Mars’s datum; and (iii) minimal steep slopes within the ellipse.
In 2014, two international workshops were held to discuss potential landing sites. The outcome
of these workshops was a shortlist of four possible sites: Aram Dorsum, Hypanis Delta, Oxia Planum
and Mawrth Vallis. We proposed the Hypanis and Aram Dorsum sites and have since further
developed their scientific cases for selection, which we here present.
C H R Y S E
P L A N I T I A
20°N
Mawrth Vallis
L U N A E
Dichoto
my bo
undary
Aram Dorsum
es
Ar
21.2
lis
10°N
l
Va
A R A B I A
T E R R A
Hypanis Delta
Elevation (km)
Latitude
P L A N U M
Chaos terrains
X A N T H E
Oxia Planum
T E R R A
-8.2
0°N
270°E
Longitude
0°E
Figure 1. The location of the four ExoMars landing site candidates that remain under consideration.
The Aram Dorsum site in western Arabia Terra (Figure 1) is situated about half way between
Meridiani Planum and the dichotomy boundary, where Arabia Terra meets the northern lowlands.
Aram Dorsum itself is an inverteda Noachian-era, aggradational, multithread/sinuous river-system,
including small tributaries and extensive flood plain-like marginal deposits. It displays clear evidence
for the long-lived action of water in the Noachian. Although the inverted channel likely contains
mainly coarse-grained sedimentary outcrops, the channel marginal unit is probably fined-grained
sediments, or could contain lenses and/or ‘islands’ of fine-grained material suitable for preserving
biosignatures.
The Hypanis landing site in northern Xanthe Terra is situated on the dichotomy boundary. Our
study area includes fluvio-deltaic deposits at the termini of nearby Sabrina Vallis and Hypanis Vallis
itself. The Hypanis deltaic system is extensive, with multiple lobes extending from the main deposit
up to ~70 km to the north and east. Rock units occupying the bulk of the landing ellipse are
interpreted as distal deltaic depositional plains because they exhibit fine-scale layering and spectral
signatures of hydrated phyllosilicates. Here, formative low-energy depositional environments may
have concentrated any potential biosignatures transported from the upstream Hypanis-Nanedi fluvial
system.
We present up to date science and engineering assessments of both sites in the approach to the
upcoming Third ExoMars Landing Site Selection Workshop in October 2015.
11 | ORAL ABSTRACTS – WED 2 SEP, MORNING – MARS | ASB6
Using rover stereo-imagery to assess the habitability of ancient aqueous environments on Mars
R. Barnes (1), S. Gupta (1), M. Giordano (2), J.G. Morley (2), J. P. Muller (3), Y. Tao (3), J. Sprinks
(2), C. Traxler (4), G. Hesina (4), T. Ortner (4), K. Sander (5), B. Nauschnegg (5), B. Huber (5), G.
Paar (5), L. Fritz (4), K. Willner (6), E. Tasdelen (7), T. Pajdla (8).
(1) Imperial College London, robert.barnes@imperial.ac.uk, (2) University of Nottingham, (3) Mullard Space Science Laboratory,
University College London, (4) VRVis Zentrum für Virtual Reality und Visualisierung Forschungs-GmbH, (5) Joanneum Research, (6) DLR
Institute of Planetary Research, (7) Technical University Berlin, (8) Czech Technical University.
On Earth, sediments and sedimentary rocks, particularly those formed by or in water, are where we
find fossil life and other preserved biosignatures. One of the prime goals of NASA’s Mars
Exploration Rovers (MER) and Mars Science Laboratory Curiosity Rover (MSL), and ESA’s 2018
ExoMars Rover is to analyse outcrops of sedimentary rocks and assess their potential for habitability
and preservation of ancient microbial life. Thus techniques and tools for analysing computer models
of sedimentary rock outcrops are crucial to developing efficient exploration strategies to employ in
the search for ancient Martian life.
Panoramic digital cameras (PanCam on MER and MastCam on MSL) serve as the 'eyes' of the rovers,
and are used for identifying suitable rock outcrops and characterising features that provide clues as
to how the rocks were originally deposited as sediments. These clues are preserved in layer
geometries, internal features within layers and the size and texture of constituent grains. On Earth
these features are understood through 3D measurements and analyses of geological features in rock
outcrops. The panoramic camera systems can take stereo images which are used to create 3D
reconstructions of rock outcrops which can be analysed much like geologists might do on Earth.
The EU-FP7-PRoViDE project has compiled all the vision data from the rover missions within a
database accessible through a web-GIS (PRoGIS) and 3D viewer (PRo3D). Stereo-imagery selected
in PRoGIS can be rendered in PRo3D, enabling the user to zoom, rotate and translate the 3D model.
Interpretations can be digitised directly onto the 3D surface, and simple measurements can be taken
of the dimensions of the outcrop and sedimentary features within it. Dip and strike is calculated
within PRo3D from mapped bedding contacts and fracture traces. Results from multiple outcrops
can be integrated within PRoGIS to gain a detailed understanding of the geological features within an
area. The tools and spatially referenced data within the PRoViDE framework allow for efficient
planning of rover traverses and drilling/sample acquisition strategies, as well as derivation of
quantitative estimates of water volumes and discharges, duration of the presence of liquid water,
relative ages of sedimentary features, and spatial distribution of important physical and geochemical
characteristics.
These tools have been tested using three case studies; Victoria Crater, Yellowknife Bay and Shaler.
Victoria Crater, in the Meridiani Planum region of Mars, was visited by the MER-B Opportunity
Rover. Erosional widening of the crater produced <15 m high outcrops which are ideal for tool
testing on Martian aeolian bedforms. Yellowknife Bay and Shaler were visited in the early stages of
the MSL mission, and provide excellent opportunities to characterise Martian fluvio-lacustrine
sedimentary features in 3D. Development of these tools is crucial to full exploitation of similar data
from future missions, particularly the 2018 ExoMars Rover PanCam.
The research leading to these results has received funding from the European Community's Seventh Framework
Programme (FP7/2007-2013) under grant agreement n° 312377 PRoViDE.
12 | ORAL ABSTRACTS – WED 2 SEP, MORNING – MARS | ASB6
Using Earth-based analogues to further our exploration of Mars
Claire Cousins (invited)
Dept. Earth and Environmental Sciences, University of St. Andrews, UK.
Contact: crc9@st-­‐andrews.ac.uk Robotic exploration of Mars is significantly guided by analogue research here on Earth. Both active
environments and ancient geological deposits can serve to define what types of biosignature to look
for during life-detection missions, and what instrumentation is necessary to explore the Martian
surface and subsurface. Within the context of astrobiology, Mars analogues can be divided into
‘geological analogues’, which offer examples of lithologies, mineral facies, and associated stratigraphic
relationships that provide a geological record of past habitability, and ‘biological analogues’, which
provide examples of active extremophile or lithotrophic microbial communities that can be explored
regarding their metabolism, resistance to extremes, and biogeochemical cycling. The latter is
particularly valuable in establishing the organic and geochemical fingerprint that these microbial
communities may leave behind in the rock record. As such, geological and biological analogues are
inherently related.
The fundamental driver behind past Martian habitats is the interaction of liquid water with basaltic
crust, which has resulted in a variety of sedimentary lithologies, alteration mineral terrains, and
diagenetic features. Globally, alteration mineral phases on Mars are dominated Fe/Mg phyllosilicates,
chlorites, Al-clays, opaline silica, zeolites, and sulfates. Terrestrial environments that encompass
these phases and associated depositional habitats therefore play a vital role in advancing the robotic
exploration of Mars. A number of Mars-analogue localities exist within the Arctic and are important
for both the geological and biological exploration of Mars. Relevant mineral deposits and terrains can
be found in central Iceland, within the active volcanic zones. Here, basaltic and hydrothermal
interaction with freshwater glacial systems create isolated environments that replicate many aspects
of the Martian surface, and the associated palaeoenvironments that may have once existed.
Hydrogen and sulfur-driven microbial communities can be found at the Kverkfjöll glaciovolcanic
system, while Pleistocene and modern fluvial-lacustrine sedimentation provides a rare terrestrial
example of basalt-derived sedimentary lithologies that replicate the Fe/Mg smectite-dominated
mineral assemblages found on Mars. The archipelago of Svalbard in the high Arctic also offers a
diverse array of Mars analogue terrains, and has been used extensively for testing MSL Curiosity and
2018 ExoMars instruments during the NASA/ESA Arctic Mars Analogue Svalbard Expedition
programme.
This talk will provide an overview of these analogue sites, including their mineralogy, microbiology,
and biosignatures, and how they have been used to scientifically develop and test Mars rover
instrumentation, such as the Panoramic Camera instrument on the 2018 ExoMars rover, and
instrument prototypes for future missions.
13 | ORAL ABSTRACTS – WED 2 SEP, MORNING – MARS | ASB6
Martian analogue samples and their spectroscopic biosignatures
Lewis R. Dartnell
Space Research Centre, Dept. Physics & Astronomy, University of Leicester, Leicester LE1 7RH
The success of an astrobiological search campaign on Mars, or other planetary bodies in the solar
system, relies upon the reliable detection of evidence of past or present microbial life, or so-called
biosignatures. While conclusive proof of life may depend on discovery of isotopic fractionation or
enantiomer bias, these methods require sample preparation and consumable resources (such as
solvent for extraction or sample wells in the instrument). Spectroscopic methods, on the other
hand, require little or no sample preparation, can be repeated essentially endlessly, and may be
performed in contact or even remotely. Such methods are therefore ideally suited for triaging for
targets containing biosignatures, which can be confirmed by supporting instrumentation. Here we
discuss the use of Raman and FTIR (Fourier Transform Infra Red) spectroscopy, both vibrational
spectroscopy methods that are complementary to each other, for the detection and characterisation
of biosignatures of microbial life colonising a diverse sample set. This sample set includes both
hypolithic and endolithic extremophile colonisation of rocks and minerals from martian analogue
sites around the world, including the Mojave desert, the Atacama desert and the Antarctic Dry
Valleys. Raman spectroscopy is sensitive to biological pigments including carotenoids, chlorophyll and
scytonemin, and FTIR reveals the presence of fatty acids and other cellular components.
14 | ORAL ABSTRACTS – WED 2 SEP, MORNING – MARS | ASB6
Detecting Polycyclic Aromatic Hydrocarbons on Mars
Jacqueline Campbell (1),(2) & Jan-Peter Muller (2)
[1] University of Brighton and (2) Mullard Space Science Laboratory, UCL
Polycyclic aromatic hydrocarbons (PAHs) are thought to be abundant throughout the universe, and
have been found to coalesce in space within dust clouds; spectral signatures indicative of PAHs
anthracene (C14H10) and pyrene (C16H10) were detected by Mulas et al. (2005) during their
investigation of infrared emissions from the Red Rectangle Nebula.
It is here hypothesised that atoms and molecules frozen within ice particles in dense molecular
clouds in space undergo processing by ultraviolet light and cosmic rays to produce more complex
PAHs. These eventually rain down on primordial planets, either directly from planetary accretion
discs, or are delivered on comets and meteorites (Allamandola, 2011). PAHs could also have been
formed in situ through Fischer-Tropsch reactions of hydrogen and carbon-monoxide rich igneous
material on early Mars (Zolotov and Shock, 1999).
The delivery of complex organic compounds to established, habitable planets via bolide impact, or in
situ formation of PAHs, is a very important concept in astrobiology, and could be instrumental in
explaining abiogenesis. Deamer et al. (2002) put forward the argument that some of these complex
molecules are amphiphilic, creating vesicles similar to cell membranes that are capable of creating a
stable, protected environment for emerging biochemistry. In addition, these membranes can trap
photoluminescent molecules formed by UV radiation, resulting in complex organic chains that are
capable of absorbing energy; a crucial step in theories on the origin of life (Dworkin et al., 2001).
PAHs could also indicate the degradation of Martian organisms (Mckay et al. 1996) and could
therefore be a biomarker for extinct or even extant life. The ability to identify PAHs using remote
sensing could prove a crucial tool in the search for extraterrestrial organisms.
Using data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on board
NASA’s Mars Reconnaissance Orbiter, research is being undertaken at the UCL Mullard Space
Science Laboratory to determine whether CRISM infrared spectra can be used to detect PAHs, with
the initial findings being presented at the conference.
References
Allamandola, L.J. PAHs and Astrobiology. (2011) PAHS and the Universe, EAS publications series, 46. 305-317.
Deamer, D. Dworkin, J.P. Sandford, S.A. Bernstein, M.P. Allamandola, L.J. (2002). The First Cell Membranes. Astrobiology, 2, 371-81
Dworkin, J.P. Deamer, D.W. Sandford, S.A. Allamandola, L.J. (2001). Self-assembling Amphiphilic Molecules: Synthesis om Simulated
Interstellar/Precometary Ices. Proc. Nat. Acad. Science. 98, 815-819
McKay, D. Gibson. E. (1996). Search for past life on Mars; possible relic biogenic activity in Martian meteorite ALH84001. Science. 273. 924-30.
Mulas, G. Malloci, C. Joblin, C. Toublanc, D. (2005) Estimated IR and phosphorescence emission fluxes for specific Polycyclic Aromatic
Hydrocarbons in the Red Rectangle. Astronomy and Astrophysics. 446. 537-49
Zolotov, M. Shock, E. (1999) Abiotic synthesis of PAHs on Mars. Journal of Geophysical Research. 104. 14033-49.
15 | ORAL ABSTRACTS – WED 2 SEP, MORNING – MARS | ASB6
Analytical protocols for the extraction of aromatic carboxylic acids from a Mars soil
analogue, containing perchlorate salts.
Kevin G Devine1 and Steven A Benner2
1
Faculty of Life Sciences and Computing, London Metropolitan University, London, UK.
2
Foundation for Applied Molecular Evolution, 1309 Progress Blvd, Alachua FL-32615, Florida, USA
The presence of perchlorate (ClO4-) salts in the soils of Mars at 0.6wt% complicates the search for
indigenous organic compounds, particularly if they are present at low concentrations (<5.00ppm).
Previous (Vikings 1&2, Phoenix) and current (Curiosity) missions have employed thermal
volatilization-gas chromatography-mass spectrometry (TV-GC-MS) to search for organics.
Perchlorate breaks down at temperatures above 300°C, yielding molecular chlorine (Cl2) and oxygen
(O2) which rapidly reacts with any organics present to yield carbon dioxide, water and simple
chlorinated organics. The latter were indeed detected by both Vikings and the SAM instrument on
board Curiosity.
Previously, we had speculated about what kind of organic compounds should be present in the
Martian regolith, which result from the photochemical oxidation of organic materials delivered by
meteoric impacts. In particular, the aromatic carboxylic acids mellitic acid, benzene-1,2-4,5
tetracarboxylic acid, trimesic acid and benzoic acid should be present at concentrations ranging from
1.0ppb to 500.0ppb. We describe herein analytical protocols for the extraction of these aromatic
acids at these concentrations from a Mars analogue soil, which contains 0.6wt% perchlorate salts.
These analytical protocols include liquid chromatography-mass spectrometry (LC-MS), and, following
derivatization of the extracted aromatic acids, gas chromatography-mass spectrometry (GC-MS).
16 | ORAL ABSTRACTS – WED 2 SEP, AFTERNOON – MARS | ASB6
The alteration history of a martian impact regolith NWA 8114
J. L. MacArthur1, J. C. Bridges1, L. J. Hicks1, R. Burgess2, and K. Joy2.
1Space
Research Centre, University of Leicester, UK. 2SEAES, University of Manchester, UK.
Contact: jm650@le.ac.uk
NWA 8114 (a pair of NWA 7034) is a polymict [1] martian regolith breccia [2] with a bulk-rock age
(Rb-Sr) of ~2.1 Ga [3]. It is the most hydrated and oxidized known martian meteorite [3]. The
oxygen isotope ratio of water shows Δ17O values above the terrestrial fractionation line and the
D/H isotope ratio analyses also support the martian origin of water in NWA 7034 [3]. We seek to
understand the role of water in the alteration of the parent martian regolith using X-ray Absorption
Spectroscopy at the Diamond Synchrotron (Beamline I18), FIB-TEM, CT Scanning and Ar-Ar dating.
Figure 1: STEM mosaic image of FIB wafer showing breakdown of pigeonite (px) to iron oxide (iron ox) and an
amorphous aluminium silicate (AlSi) material.
Our work has classified different clasts and focused on zonation in pyroxene clasts, which is often
associated with the clast having a feldspathic border. We have characterised the partial breakdown
and mantling by fine-grained material, of a pigeonite clast Wo12-18En30-34Fe47-56 and low-Ca pyroxene
clast Wo2En65-68Fs29-33, in terms of their oxidation state and related textures. Fe-K XANES analysis
has shown these to be more oxidised than other pyroxenes found in NWA 8114, up to 25% Fe3+/
ΣFe, while STEM images (Figure 1) and TEM EDX data have found the pyroxene to have partially
broken down to a submicron mixture of iron oxide together with an amorphous aluminium silicate
material. The CT scan shows more of the large pigeonite clast as well as an intact spherical clast
which shows accretion of different layers.
We have carried out 40Ar-39Ar dating on three separated feldspar clasts and one augite clast. The
pyroxene clast shows ages in the range 1100-1250 Ma, whereas the feldspar clasts show more varied
values.
We hypothesise that this martian impact regolith was subject to an impact-induced hydrothermal
system causing the oxidation and alteration seen at temperatures up to 900°C. NWA 8114 will
improve our understanding of the conditions at an impact crater on Mars [4] which has ramifications
for the potential of life having existed in hydrothermal systems at craters.
References: [1] Stephen N.R and Ross A.J. (2014) LPSC XLIV, Abstract #2924. [2] Humayun, M. et al. (2013)
Nature 503, 513-516. [3] Agee C. B. et al. (2013) Science 339, 780-785. [4] Schwenzer S.P. and Kring D.A.
(2013) Icarus 226, 487-496.
17 | ORAL ABSTRACTS – WED 2 SEP, AFTERNOON – MARS | ASB6
Organic records in impact excavated rocks on Mars
1
2
1
W. Montgomery , G. D. Bromiley , and M. A. Sephton
1
Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering,
Imperial College London, SW7 2AZ, UK.
2
School of GeoSciences, University of Edinburgh, Grant Institute, West Main Road, Edinburgh EH9
3JW, UK.
Contact: w.montgomery@imperial.ac.uk
Impact ejected rocks are targets for life search missions to Mars(1), because the Martian surface is
recognized as inhospitable to life’s remains(2). Impact events bring materials to the surface where
they may be accessed without complicated drilling procedures(3). On Earth, different assemblages of
organic matter types derive from varying depositional environments. We assessed whether these
different types of organic materials can survive impact events without corruption. We subjected four
terrestrial organic matter types in typical mineral environments to elevated pressures and
temperatures in piston- cylinder experiments followed by chemical characterisation using wholerock pyrolysis-gas chromatography-mass spectrometry.
Our data reveal that long chain hydrocarbon-dominated organic matter types are unresistant to
pressure whereas aromatic hydrocarbon-dominated organic matter types are relatively resistant.
These observed chemical responses to pressure suggest that the impact excavated record of biology
on Mars will be unavoidably biased, with microbial organic matter underrepresented while
metamorphosed, degraded or abiotic meteoritic organic matter types will be selectively preserved.
The effects of pressure on the fidelity of organic records of past Martian biology must be appreciated
for future life detection missions to the red planet.
1. C. S. Cockell, N. G. Barlow, Impact Excavation and the Search for Subsurface Life on Mars. Icarus
155, 340-349 (2002).
2. R. W. Court, M. A. Sephton, J. Parnell, I. Gilmour, The alteration of organic matter in response to
ionising irradiation: Chemical trends and implications for extraterrestrial sample analysis.
Geochimica et Cosmochimica Acta 70, 1020-1039 (2006).
3. H. J. Melosh, A. M. Vickery, W. B. Tonks, in Protostars and Planets III, E. H. Levy, J. I. Lunine, Eds.
(University of Arizona Press, Tuscon, AZ, 1993), pp. 1339-1370.
18 | ORAL ABSTRACTS – WED 2 SEP, AFTERNOON – MISSIONS/INSTRUMENTS | ASB6
Aurora national programme overview and future funding opportunities
Charlotte Blake-Kerry, UK Space Agency
The UK Space Agency is responsible for the Aurora national programme, previously funded by the
Science and Technology Facilities Council. The programme is focused on exploration by non-manned
spacecraft of regions of space where in the future humans may one day live e.g. the Moon, Mars or
Asteroids and funds both industry and academia in the fields of planetary science, astrobiology, space
instrumentation and the development of new technologies to exploit the opportunities of space
missions.
As we prepare for ExoMars 2016 and 2018, the Agency is looking to move towards exploitation of
this mission, therefore the balance of future funding is changing.
Running alongside, the Agency is now looking to the future, post-ExoMars; the next mission towards
the goal of Mars Sample Return.
19 | ORAL ABSTRACTS – WED 2 SEP, AFTERNOON – MISSIONS/INSTRUMENTS | ASB6
Planetary protection for life detection missions
Gerhard Kminek (invited), European Space Agency
In the year just before the launch of Sputnik scientists expressed their deep concern that the
exploration of space might compromise future scientific investigations if no appropriate measures
are put in place. Responding to this concern, the International Council of Scientific Unions (ICSU)
formed an ad-hoc Committee and issued the first rules for planetary protection in the autumn of
1958. Subsequently, the newly established Committee On Space Research (COSPAR) of the ICSU
was given the responsibility to formulate and maintain more detailed planetary protection
requirements.
Since that time missions into the solar system have to meet planetary protection requirements to
different degrees, depending where they go and what they do. The most stringent requirements are
naturally for missions that search for life. The last, and so far only, time that these stringent
requirements had to be applied to a mission was during the Viking program in the 70s. Now, several
decades and multiple missions to Mars later, ExoMars 2018 is stepping up to the challenge and
explicitly will search for life on Mars again. This presentation will describe how the planetary
protection requirements will ensure the scientific integrity of the life-detection investigations
planned for the ExoMars 2018 mission.
20 | ORAL ABSTRACTS – WED 2 SEP, AFTERNOON – MISSIONS/INSTRUMENTS | ASB6
Novel fluorescent sensors for the detection of organic molecules in extra-terrestrial
samples
Roy C. Adkin1, James I. Bruce2 and Victoria K. Pearson1,
1Department
of Physical Sciences, 2Department of Life, Health and Chemical Sciences, The Open
University, Walton Hall, Milton Keynes, Buckinghamshire, The United Kingdom, MK7 6AA
Contact: Roy.Adkin@open.ac.uk; Twitter: @RCAdkin; +44 (0)1908858372
Introduction: Organic compounds in extra-terrestrial samples have mostly been elucidated by
destructive analytical techniques [1 and references therein] which remove any information regarding
spatial relationships between minerals and organic species. These relationships may infer the
cosmological provinces in which organic chemical evolution took place. We will describe progress
towards developing fluorescent sensors that may identify such prebiotic molecules in aquo with a
view to future in situ application in order to resolve spatial discrimination and therefore the origins
of organic species.
Rationale: Lanthanide (Ln) elements such as europium (Eu) produce well-defined line-like, high
intensity (Figure 1) and long lived fluorescent emissions [2], which may alter on interactions with
organic molecules. In order to develop a sensor based on these principals, the Ln atom needs to be
rendered chemically inert while remaining susceptible to these organic molecule interactions. An
organic ligand must be employed to attain this. DOTA and DO3A (1,4,7,10tetraazacyclododecanetetracetic/triacetic acids, respectively), were chosen as a plausible organic
ligands because their structure and ability to chelate are well characterized. They are also
commercially available. Fluorescent Ln-DOTA/DO3A complexes are used in many biological and
analytical imaging applications [3, 4] so it is logical to investigate their applicability to fluorimetric
analysis of extra-terrestrial organics. Ln-DOTA complexes are very stable [5, 6] because the Ln
atom is enveloped within the four armed, tetra-substituted, cyclen ring DOTA structure. This is
advantageous because once in solution is unlikely to dissociate and therefore become chemically
reactive toward target analytes. The disadvantage of this is that the Ln is entirely shielded from any
analyte, resulting in little or no analyte/Ln interaction. The tris-substituted cyclen ring, DO3A, which
has one less ethanoate pendant arm than DOTA, is less stable, as a result, but is less shielded
affording greater scope for interactions. Experimental procedures were designed to investigate these
theoretical advantages and disadvantages.
Methodology: A range of compounds were chosen
giving a good representation of the organics identified in
extra-terrestrial samples and most likely to interact with
the Eu ion based upon their structure. Baseline
fluorescent spectra were obtained and compared against
EuDOTA and EuDO3A/analyte mixtures at equimolar
concentrations of 1 mM to establish proof of interaction.
Results and discussion: Results showed no increase in
fluorescent intensity for either EuDOTA or EuDO3A
when any analyte was added to the solution. Increase in
intensity may be, in this case, due to reduction of
fluorescent quenching by means of displacing water
Figure 1. Fluorescent emission spectra of EuDOTA and EuDOTA + adenine (top) and EuDOTA and EuDO3A + adenine (bottom) at equimolar concentrations of 1 mM, for comparison. 21 | ORAL ABSTRACTS – WED 2 SEP, AFTERNOON – MISSIONS/INSTRUMENTS | ASB6
molecules from the complex coordination sphere indicating a Ln/analyte interaction. Figure 1 shows
spectra obtained for EuDOTA (top) and Eu DO3A (bottom) and those when (L)-serine is added as
the analyte. The lack of interactions between the analytes and EuDOTA/EuDO3A may be due to the
sensor structure; the first coordination sphere geometry for Ln is eight-coordinate. It is, therefore,
most likely that the four nitrogen atoms of the cyclen ring and the four ethanoate pendant arms of
the DOTA molecule occupy all eight coordination points. This reduces the ease with which the
analyte can approach the Eu atom minimising any changes in fluorescent signal. DO3A also showed
no evidence of analyte interaction. Reducing the number of pendant arms would reduce complex
stability markedly so the use of a bis-substituted cyclen, DO2A, is not planned.
Conclusion: We have proven the application of EuDOTA and EuDO3A complexes in the detection
of organic molecules in carbonaceous chondrites at the concentrations observed in authentic extraterrestrial samples is unlikely to be successful. Experimentation has shown that neither Eu complex
exhibited an increase in fluorescent intensity; it is, therefore, the ligand that requires modification.
To that end, a synthesis procedure has been developed to produce a ligand molecule with the
stability of DOTA but with labile functional groups that can incorporate light harvesting molecules.
These molecular appendages are capable of absorbing light at a wavelength lower than the excitation
wavelength of the Ln atom. The emission wavelength of this molecule, however, is close to that of
the Ln atom excitation; the Ln atom will absorb the emission. This process of intermolecular energy
transfer is termed the ‘antenna effect’ and can be utilised to increase the sensor sensitivity by
increasing its intrinsic fluorescent intensity. This molecule will chelate Eu ions in the same manner,
and will be treated with the same analytes and analytical methodology, as described above. We will
present an overview of the EuDOTA and EuDO3A results and discuss the development and
preliminary testing of the modified ligand to date.
References: [1] Pearson, V.K., et al., (2010) Astrobiology: Emergence, Search and Detection of Life, Basiuk,
V.A., Editor, Am. Sci. Pub., 155-173. [2] Bruce, J. I., (2001) Photophysical aspects of lanthanide (III) complexes.
[3] Schäferling, M., (2012) Angewandte Chemie Int. Ed., 51, 3532-3554. [4] Faulkner, S., et al., (2005) App.
Spec. Rev., 40, 1-31. [5] Bruce, J. I, et al. (2000) J. Am. Chem. Soc., 122, 9674-9684. [6] Armelao, L., et al.,
(2010) Coord. Chem. Rev., 254, 487-505.
22 | ORAL ABSTRACTS – WED 2 SEP, AFTERNOON – MISSIONS/INSTRUMENTS | ASB6
CubeSat and CubeSat-like payloads for astrobiology, fundamental biology and human
cell biology studies
David Cullen, Cranfield University
Access to space environments (primarily for exposure to microgravity and/or space radiation) to
study a wide range of biological issues is often restricted by long-lead times, infrequent flight
opportunities and high costs using traditional space platforms. CubeSats and similar approaches
offers the possibility of reduced lead-times, more frequent flight opportunities and reduced mission
costs but with compromises of reduce experiment mass, volume, power and data budgets. To date
there has been a limited number of relevant CubeSat flights with bioscience payloads (GeneSat-1,
PharmaSat, O/OREOS and SporeSat) but these have successfully demonstrated the potential for
flying bioscience experiments on CubeSats.
Cranfield University together with partners have been developing the BAMMsat concept –
“Bioscience, Astrobiology, Medicine and Materials Science on CubeSats”. This involves a hardware design
adaptable for a broad range of applications and where common features are the abilities to: (i) house
multiple samples, (ii) maintain the samples in an appropriate local environment, (iii) appropriately
perturb the samples and (iv) monitor the samples before, during and after perturbance.
At present an end-to-end BAMMsat payload breadboard is under development with a goal of
demonstrating the ability to fly and study human cell cultures in space. Successful demonstration of
this would open the use of CubeSat platforms for the study of human cell biology in space in
contexts associated with increasing the understanding of issues associated with long-term exposure
of humans to space environments as well as elaborating aspects of fundamental cell biology
processes associated with an aging and diseased Earth population.
This on-going work has also led to the realisation that in addition to free-flying CubeSats, the
advantages of miniaturised CubeSat payloads have benefits for use on other space platforms
including both inside and outside the ISS, on other established space platforms and emerging
platforms such as commercial sub-orbital vehicles. Two examples of CubeSat-like payload
approaches, with present author involvement, have been the recent success of the DLR (Germany)
led ICEcube (simulating icy moon environments) and the Royal Botanic Gardens Kew (UK) led
GENESIS (understanding the issues of exposure of plant seeds to space environments) consortia
proposing CubeSat-like payload experiments for the ILSRA-2014 call for ISS experiments. Both are
proposing to house samples in CubeSat-like payloads for mounting outside the ISS and allowing in
situ monitoring of samples during extend exposure.
These examples, their current status and the issues and potential associated with these and similar
approaches will be described in the presentation.
23 | ORAL ABSTRACTS – WED 2 SEP, AFTERNOON – EXOPLANET SPECIAL | ASB6
Prospects to identify habitable environments in our Galaxy through remote sensing
spectroscopy
Giovanna Tinetti (invited), University College London
The acquisition of spectroscopic data of the Earth’s atmosphere from artificial satellites has changed
our perception of terrestrial life and has provided, for the first time, a rigorous scientific
framework to search for life elsewhere in our Galaxy. Seen from the outside, our planet appears to
be similar, in some aspects, to other planets, yet it shows distinctive signatures of a life-hosting
planet, which cannot be found elsewhere in the Solar System. Lovelock (1965) suggested to search
for the presence of compounds in the planet’s atmosphere which are incompatible on a longterm
basis, i.e. in chemical disequilibrium – for example, oxygen and hydrocarbons co-exist in the Earth’s
atmosphere. While being the only recipe of biosignature currently available, is that a robust one?
The discovery of planets around other stars will offer in the next decades the chance to test this
hypothesis outside the boundaries of our Solar System. While the number of discovered planets
located at the right distance to the star to host some liquid water is increasing by the day, are those
objects really habitable or inhabited?
From the little we know about these alien worlds, it appears we need to progress further in the
understanding of galactic planetary science before we can commit to a conclusive answer
concerning habitability. In this talk I will review the current knowledge about exoplanets and discuss
what are, in my view, the necessary steps to be taken in the future to address the question of
planetary habitability.
24 | ORAL ABSTRACTS – THU 3 SEP, MORNING – COSMOCHEMISTRY/METEORITES | ASB6
Complex Organic Molecules in star forming regions
Serena Viti (invited), University College London
Complex Organic Molecules (COMs) are now routinely observed in the Interstellar Medium, around
massive protostars, in the so called “hot cores”, as well as in low-mass star forming regions, (“hot
corinos”).
In this talk I will give an overview of the chemical complexity observed in space with particular
emphasis on their astrobiological significance: in massive star forming regions COMs trace the most
compact region, where the protostar and (proto-planetary) disk form; COMs can be divided in
subgroups, depending on their interrelationship during formation and destruction: ratios of COMs
are very time dependent and hence could be used as evolutionary indicators, very much needed for
the understanding of the early phases of massive star formation. In solar-like nebulae the importance
of COMs may be related to the origin of life and there are now several efforts made to detect
glycine in regions where solar-like stars form.
I will finally discuss the possible formation routes of COMs and highlights the needs astronomers
have of experimental data including accurate rest frequencies, temperature dependent intensities, as
well as rate coefficients for all their gas and solid phase formation routes.
25 | ORAL ABSTRACTS – THU 3 SEP, MORNING – COSMOCHEMISTRY/METEORITES | ASB6
Early delivery of Carbon to the Earth under reducing conditions
Hilary Downes
Centre for Planetary Sciences UCL/Birkbeck; Dept of Earth Sciences Natural History Museum
London
It is often considered that the early Earth went through a “Magma Ocean” stage, during which all
volatile elements were depleted by high temperature degassing. According to this model, a late
veneer of chondritic material was added to the Earth after the formation of the Moon, bringing the
volatile elements such as carbon, nitrogen, phosphorus and sulphur with it. This is often referred to
as the “Late Veneer”. Independent evidence for addition of volatile-rich material to the inner solar
system comes from studies of 4 Vesta, on which about 5% of the surface is composed of
carbonaceous chondrite material which has accreted to the asteroid after the end of crust
formation.
This scenario assumes that all of the material which accreted to the Earth was in an oxidised state,
i.e. as broadly represented by the Murchison meteorite (a primitive carbonaceous chondrite which
fell in Australia in 1969 which contains abundant carbon in the form of organic compounds including
amino acids). However, recent models have suggested that early Earth accreted under more
reduced conditions and gradually became more oxidised. Under such early reducing conditions,
many elements which would normally be considered to be volatile can behave in more refractory
ways. Carbon may have been delivered as pure graphite or diamond, both phases being relatively
common in some meteorites. Diamond’s main impurity is nitrogen and traces of primordial nitrogen
have been found in terrestrial mantle diamonds. Even at the present day, some interplanetary dust
particles and micrometeorites are found to consist of ~50% carbon.
Even in relatively recent periods in Earth history, extraterrestrial material consisting mainly of
diamond with minor nitrides has been delivered to Earth (e.g. carbonado). Phosphide and nitride
minerals also occur in some meteorites. A recent find of a diamond pebble of extraterrestrial origin
which fell to Earth 28.5 Ma ago in northern Africa also suggests that Earth may have acquired much
of its inventory of so-called “volatile” elements as reduced phases.
26 | ORAL ABSTRACTS – THU 3 SEP, MORNING – COSMOCHEMISTRY/METEORITES | ASB6
The amino acid and hydrocarbon contents of the Paris meteorite, the most primitive
CM chondrite
Z. Martins1, P. Modica2, B. Zanda3, L. Le Sergeant d'Hendecourt2
1Dept
of Earth Science and Engineering, Imperial College London, South Kensington Campus,
London SW7 2AZ, UK, 2CNRS - Université Paris XI, Institut d’Astrophysique Spatiale, ‘‘Astrochimie
et Origines’’, FR 91405 Orsay Cedex, France, 3Muséum d’Histoire Naturelle, CNRS, 61 rue Buffon,
75005, Paris, France.
Contact: z.martins@imperial.ac.uk
Introduction: The Paris meteorite is the least aqueously altered CM chondrite analysed to date [13] with only weak thermal metamorphism [2, 4-6]. In addition, the IR spectra of some of the
fragments of the Paris meteorite indicate a primitive origin for its organic matter [7]. Aqueous
alteration on the CM parent body does not seem to influence significant modification on the
insoluble organic matter (IOM) phase of Paris [8]. In order to determine the effect of aqueous
alteration on the abundance and distribution of meteoritic soluble organic matter, we have analysed
for the first time the amino acid and hydrocarbon contents of the Paris meteorite [9].
The amino acid content of Paris: Our data shows that the isovaline detected in the Paris
meteorite is racemic within the experimental error (corrected D/L = 1.03; corrected L-enantiomer
excess (%) = -1.4 ± 2.6) [9]. In addition, the Lee for isovaline values increase from -1.4 ± 2.6% for
the least aqueously altered CM Paris, to 16.5 ± 7.5% for the most aqueously altered CM Scott
Glacier (SCO) 06043 [9]. Our data supports the hypothesis that aqueous alteration is responsible
for the high L-enantiomer excess of isovaline observed in the most aqueously altered carbonaceous
meteorites [10,11], i.e. aqueous alteration does not create by itself an isovaline asymmetry, but it
may amplify a small enantiomeric excess. Paris has also the lowest relative abundance of βalanine/glycine (0.15 ± 0.02) for a CM chondrite, which fits with the relative abundance of βalanine/glycine increasing with increasing aqueous alteration [12,13]. In fact, extensive aqueous
alteration in the parent body of carbonaceous meteorites may result in the decomposition of αamino acids and the synthesis of β- and γ-amino acids [14-16].
The hydrocarbon content of Paris: The Paris meteorite contains aliphatic hydrocarbons (nalkanes) ranging from C16 to C25, with no even or odd number predominance. It also contains 3- to
5-ring non-alkylated polycyclic aromatic hydrocarbons (PAHs) [9]. No alkylated PAH is present in
the Paris meteorite, supporting the hypothesis that higher relative abundances of alkylated PAHs
correlates with a higher degree of aqueous alteration on the meteorite parent body of CM2
chondrites [17].
References: [1] Blanchard I. et al. (2011) Meteoritics & Planet. Sci., 46, A21. [2] Caillet Komorowski C. et
al. (2011) Meteoritics & Planet. Sci., 46, A35. [3] Cournède C. et al. (2011) Meteoritics & Planet. Sci., 46, A50. [4]
Kimura M. et al. (2011) Meteoritics & Planet. Sci., 46, 431-442. [5] Bourot-Denise M. et al. (2010) LPS XLI,
Abstract #1533. [6] Merouane S. et al. (2011) Proceedings EPSC-DPS Joint Meeting, 902. [7] Merouane S. et al.
(2012) ApJ, 756, 154-160. [8] Remusat L.et al. (2011) Meteoritics & Planet. Sci., 46, A197. [9] Martins Z. et al.
(2015) Meteoritics & Planet. Sci., 50, 926-943. [10] Glavin D. P. and Dworkin J. P. (2009) PNAS, 106, 5487-5492.
[11] Pizzarello S. et al. (2003) GCA, 67, 1589-1595. [12] Glavin D.P. et al. (2006) Meteoritics & Planet. Sci., 41,
889-902. [13] Glavin D.P. et al. (2010) Meteoritics & Planet. Sci.45, A64. [14] Botta O. et al. (2007) Meteoritics &
Planet. Sci., 42, 81–92. [15] Martins Z. et al. (2007) Meteoritics & Planet. Sci., 42, 2125-2136. [16] Cooper G.W.
and Cronin J.R. (1995) GCA, 59, 1003–1015. [17] Elsila J. E. et al. (2005) GCA, 5, 1349-1357.
27 | ORAL ABSTRACTS – THU 3 SEP, MORNING – COSMOCHEMISTRY/METEORITES | ASB6
First in-situ analysis of amino acids in the Murchison meteorite with C60-TOFSIMS
T. Henkel and I. C. Lyon.
The University of Manchester, SEAES, Oxford Road, Manchester, M13 9PL, United Kingdom
Contact: torsten.henkel@manchester.ac.uk
Introduction: Primitive meteorites were a main contributor of organic material to the early Earth.
Amino acids from meteorite infall in particular may have played a role in the formation of life.
Previous work characterising the organic matter in meteorites [e.g. 1] has almost exclusively been
carried out on bulk samples with the organic material extracted from the meteorite. Previous
studies have also shown that the extraction process can alter the abundances of amino acids [2] and
that it is unclear whether amino acids found in meteorites are, at least partially, produced in the
extraction process [3].
To avoid these problems in this study, amino acids were analysed in-situ using C60-time-of-flight
secondary ion mass spectrometry (C60-TOFSIMS). C60 primary ions produce molecular secondary
ions with high efficiency and little fragmentation. Depth profiling is also possible.
Sample: The analysed sample stems from a fragment of the Murchison meteorite in our collection
at the University of Manchester. A small piece was broken off to expose a fresh surface for analysis.
This surface was not coated or analysed by other techniques, which could have contaminated it
before the C60-TOFSIMS analysis. Several areas with sizes from 100-250µm were studied.
Instrumentation: Our C60-TOFSIMS instrument is described in more detail in [4,5]. Recording a
whole mass spectrum up to mass 2000 allows for parallel detection of almost all organic matter
found in primitive meteorites and mapping it with a spatial resolution of 2-3µm. A mass resolution of
up to 5000 together with a mass accuracy of a few tens of ppm al- lows for the unambiguous
identification of organic molecules.
Results: We have identified several amino acids in the analysis of fresh sample surfaces from the
Murchison meteorite. The spatial distributions of these amino acids show a correlation with the Mgdistribution in both areas.
The abundance pattern for Alanine, Aminobutyric Acid, Proline, Valine and Glutamic Acid in both
areas is similar to the relative abundances previously reported [6] with the exception of Proline,
which is very high in our sample. We also detected Serine, Cysteine, Methionine and Phenylalanine,
which haven’t been reported previously whilst not detecting Glycine and Aspartic Acid which have
been reported elsewhere [6].
Discussion: Although TOFSIMS is not able to differentiate enantiomers to test for racemic
composition; the similarity of the abundance pattern would suggest that the amino acids are indeed
indigenous and not contamination. The spatial correlation with Mg could suggest that Mg might have
played a role in the formation or alignment of these amino acids. Mineral surfaces have been shown
to specifically interact with certain organic molecules [7,8] but further analyses are necessary to
confirm if and how Mg, or the corresponding mineral, has played a role.
References: [1] Sephton, M. A. 2002. Natural product reports 19:292-311. [2] Cronin J. R. and Moore C. B.
1971. Science 172:1327-1329. [3] Burton, A. S. et al. 2012. Chem. Soc. Rev. 41:5459-5472. [4] Henkel, T. et al.
2007. Rev. of Sci. Instr. 78:055107. [5] Henkel, T. et al. 2009. Rapid Com. in Mass Spec. 23:3355-3360. [6]
Wolman Y. et al. 1972. Proc. Nat. Acad. Sci. 69:809-811. [7] Valdre, G. 2007. Eur. J. Mineral. 19:309-319. [8]
Wogelius R. A. et al. 2007. Eur. J. Mineral. 19:297-307.
28 | ORAL ABSTRACTS – THU 3 SEP, MORNING – COSMOCHEMISTRY/METEORITES | ASB6
Irradiation of organic materials in the presence of lunar minerals: can biomarkers from
the early Earth survive on the Moon?
1
2
3
4
Richard Matthewman , Ian A. Crawford , Adrian P. Jones , Katherine H. Joy , and Mark A.
1
Sephton .
1
2
Department of Earth Science and Engineering, Imperial College London, UK. Department of Earth and
3
Planetary Sciences, Birkbeck College, University of London, UK. Department of Earth Sciences, University
4
College London, UK. School of Earth, Atmospheric, and Environmental Sciences, University of Manchester,
UK.
Introduction: The organic record of the early Earth >3.8 Ga has been lost to the processes of
plate tectonics and erosion. Impacts on the Earth at and before this time would have ejected
material into space, and some of this material could have been captured by the Moon. Terrestrial
organic material, transported to the Moon in this manner, may remain preserved in layers of regolith
protected by lava flow layers [1, 2]. We have performed irradiation experiments to determine the
effects of solar energetic proton (SEP) radiation on organic material in the interval before it is
entombed by lava flow layers. Specifically, we have tested to see whether the presence of lunar
regolith minerals during irradiation has any kind of deleterious effect.
Experimental: Organic biomarkers, amino acids, and poly(styrene-co-divinylbenzene) polymer
were mixed with lunar regolith analogue JSC-1, powdered lunar meteorite MAC88105, or were
used in isolation. One polymer sample was also immersed in water. Samples flame sealed in
evacuated glass tubing were irradiated with protons using a MC40 Scanditronix cyclotron with
fluencesof3x1013 or2x1014 and energy ~4–13 MeV. Irradiated samples were analysed by gas
chromatography-mass spectrometry (GC-MS) and pyrolysis-GC-MS for the polymer samples. Amino
acid samples were derivitized with BSTFA and pyridine prior to analysis.
Results and Discussion: Partial derivitization of the amino acids precluded accurate quantification,
however the recoveries of the 5 compounds used was high (see Figure). This indicates that amino
acids are not strongly affected by proton radiation in the conditions used. The presence of lunar or
analogue minerals did not appear to affect recoveries.
The quantified recoveries of the biomarkers were also high, again indicating that the radiation has
not had a strong deleterious effect on the molecules. Further, there were no compounds detected in
the biomarker extracts which might have indicated fragmentation. Some compounds had slightly
lower recoveries than others; this can be attributed to absorption on the glass surfaces of the
experimental equipment. The presence of a mineral matrix did not appear to affect recoveries
between compounds or samples; the pattern of compound recoveries was the same as the sample
where no matrix was used.
The poly(styrene-co-divinylbenzene) likewise showed no significant response to the radiation from
the pyrolysis-GC-MS results. However, one polymer sample subjected to the higher fluence showed
slight discoloration suggesting chemical alteration, however this was not observable in the
chromatogram data. The presence of water also had no detectable influence.
29 | ORAL ABSTRACTS – THU 3 SEP, MORNING – COSMOCHEMISTRY/METEORITES | ASB6
GC-MS total ion chromatogram of the derivitized spiked amino acids recovered from proton-irradiated lunar
meteorite MAC88105. Peaks are derivitized versions of A: L- alanine; B, C: Glycine; D: L-aspartic acid; E: Lglutamic acid; F: L-Phenylalanine.
Conclusions: A range of biomarker, amino acid, and polymer compounds showed no major
detectable changes following proton irradiation. This indicates that the compounds tested are
relatively robust, and could potentially survive a minimum of 10s of thousands of years in such a
radiation environment within lunar regolith materials. However, we were only able to simulate a
limited energy range of protons, and it will be necessary to perform simulation of all types of solar
radiation experienced at the lunar surface, especially the low energy but high fluence solar wind
protons, as well as increasing duration.
References: 1. Crawford, I.A., et al., Lunar palaeoregolith deposits as recorders of the galactic
environment of the Solar System and implications for astrobiology. Earth Moon and Planets, 2010.
107(1): p. 75-85. 2. Matthewman, R., et al., The Moon as a Recorder of Organic Evolution in the
Early Solar System: A Lunar Regolith Analog Study. Astrobiology, 2015. 15(2): p. 154-168.
30 | ORAL ABSTRACTS – THU 3 SEP, MORNING – ORIGINS OF LIFE | ASB6
Clues from bioenergetics to the origin of life
Nick Lane (invited), University College London
There is a paradox at the base of life. Membrane bioenergetics - the use of ion gradients across
membranes to drive carbon and energy metabolism - are universal, but membranes are not. Radical
differences between bacteria and archaea in membrane chemistry and active ion pumping suggest
that LUCA, the last universal common ancestor, may have used natural proton gradients in alkaline
hydrothermal vents to drive growth. I will outline a possible scenario for the origin of life in this
environment, and present some experimental and modelling results which suggest that proton
gradients could have driven the transition from geochemistry to biochemistry, and the deep
divergence of archaea and bacteria.
31 | ORAL ABSTRACTS – THU 3 SEP, MORNING – ORIGINS OF LIFE | ASB6
On the biogenic origins of homochirality
Victor Sojo, CoMPLEX / Genetics, Evolution & Environment, University College London
Homochirality, the single-handedness of optically asymmetric chemical structures, is present in all
major biological macromolecules. Terrestrial life’s preference for one isomer over its mirror image
in D-sugars and L-amino acids has both fascinated and puzzled biochemists for over a century. But
the contrasting case of the equally fundamental phospholipids has received less attention. Although
the phospholipid glycerol headgroups of archaea and bacteria are both exclusively homochiral, the
stereochemistries between the two domains are opposite. Here I argue that the reason for this
“dual homochirality” was a simple evolutionary choice at the independent origin of the two
synthesizing enzymes. More broadly, this points to a trivial biogenic cause for the evolution of
homochirality: the enzymatic processes that produce chiral biomolecules are stereospecific in
nature. Once an orientation has been favoured, shifting to the opposite is both difficult and
unnecessary. Homochirality is thus the simplest and most parsimonious evolutionary case.
32 | ORAL ABSTRACTS – THU 3 SEP, MORNING – ORIGINS OF LIFE | ASB6
Acetyl phosphate as the first energy currency
Alexandra Whicher, Eloi Camprubi, Barry Herschy, and Nick Lane
Department of Genetics, Evolution and Environment,
University College London, Gower Street, London WC1E 6BT
Adenosine triphosphate (ATP) is universally conserved as an energy currency, which drives
metabolism via phosphorylation and condensation reactions. It is unlikely that ATP would have
played this role at the origin of life as it is a complex molecule whose synthesis usually depends on
sophisticated proteins (1). What moiety might have driven these dehydration reactions in water
before ATP is unknown. While phosphorylations and condensations have been accomplished under
prebiotic conditions previously, these dehydration reactions have relied on high temperatures (2),
low water activity (3), alternative solvents such as formamide(4), or abiological dehydrating agents
such as cyanamide (5-8), leading to the suggestion that life might have started on Mars where there
was less water. Here we show that acetyl phosphate (AcP), which is still used as an equivalent to
ATP in bacteria (9), can drive both phosphorylation and condensation reactions at mild
temperatures in water. AcP can be formed from thioacetate and inorganic phosphate under ambient
conditions, and reacts over minutes to hours, depending on the temperature, pH and specific ions
present. It will phosphorylate the sugar ribose to ribose-5 phosphate, drive the synthesis of the
nucleoside adenosine from ribose-5 phosphate and adenine, and phosphorylate adenosine to form
the nucleotide adenosine monophosphate. It also has a remarkable ability to condense the amino
acid glycine in water. Related work shows that small organics can be concentrated by at least 5000fold in open microporous hydrothermal systems, converting low yields into high concentrations (10).
These results show that AcP could have driven prebiotic chemistry in a similar fashion to ATP, giving
a credible link between prebiotic chemistry and modern biochemistry.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
de Duve, C. Nature 433, 581–82 (2005).
Yamagata, Y., Watanabe, H., Saitoh, M. & Namba T. Nature 352, 516–519 (1991).
DeGuzman, V., Vercoutere, W., Shenasa, H. & Deamer, D. J Mol Evol 78, 251–262 (2014).
Costanzo, G et al. J Biol Chem 282, 16729–35 (2007).
Rabinowitz, J. Flores, J., Kresbach, R. & Rogers, G. Nature 224, 795–796 (1969).
Lohrmann, R. & Orgel, L.E. Science 161, 64–66 (1968).
Liu, R. & Orgel, L.E. Nature 389, 52–54 (1997).
Leman, L., Orgel, L. & Ghadiri, M.R. Science 306, 283-86 (2004).
Martin, W. & Russell, M.J. Phil Trans Roy Soc Lond B 362, 1887–1925 (2007).
Herschy, B. et al. J Mol Evol 79, 213–227 (2014).
33 | ORAL ABSTRACTS – THU 3 SEP, MORNING – ORIGINS OF LIFE | ASB6
Peptide and proto-cell formation driven by the same energy currency system
Bryant, D. E.1, Kee T. P.1
1
University of Leeds, School of Chemistry, Woodhouse Lane, Leeds, West Yorkshire, LS2 9JT, UK
Contact: d.bryant@leeds.ac.uk.
Several routes have thus far been identified for the prebiotically plausible formation of peptide
bonds, essentially a dehydration, usually involving surfaces or activating agents. Notable among these
is the “salt induced peptide formation” (SIPF) proposed by Bernd Rode (1) in which a preference is
found for a given amino acid sequence in peptide bond formation.
We have proposed the phosphorus anhydride, pyrophosphite, as a prebiotically plausible energy
currency molecule (2) and we find it to be an efficient agent for the coupling of amino acids to form
peptides and with a distinct bias in primary sequence under pH control. In addition the coupling of
serine does not occur using pyrophosphite due to the interference of the side chain alcohol yet
peptides can be formed including serine provided the serine does not form the N terminus. The
same energy currency molecule also affords amphiphile formation via phosphonylation of long-chain
alcohols which subsequently form self-assembled structures when dispersed in aqueous phase, again
under mild conditions.
1. J. Bujdak and B.M. Rode, Catalysis Letters Vol. 91, Nos. 3–4, December 2003
2. D.E.Bryant et al. Geochimica et Cosmochimica Acta 109 (2013) 90–112.
34 | ORAL ABSTRACTS – THU 3 SEP, MORNING – ORIGINS OF LIFE | ASB6
Hypothesis: network of RNAs and their influence on life
Sohan Jheeta, Chairman: NoR HGT & LUCA, UK
Contact: sohan7@ntlworld.com
Non-coding (nc)RNAs can either be used directly for their intended purpose without further
processing, as in synthesis of ribosomes from rRNAs (eg 5S RNAs); or they can self-splice during
synthesis of a mature mRNA from a pre-mRNA, an activity displayed by interons of group I and II in
eukaryotes; ncRNAs can also be processed by other ‘ncRNA nano-machines’ such as spliceosomes
which are involved in stitching together exons so as to make complete, mature, mRNA from premRNA. Spliceosomes being composed of small U1, U2, U4/U6 and U5 RNAs and associated
proteins. In addition ncRNA can be processed by enzymes, for example dicer RNase shreds long-dsncRNAs into smaller double stranded microRNAs (ds-miRNA); these then go on to form two ssmiRNAs, termed guided and passenger miRNAs. The former is used to degrade the mRNA via a
RNA-induced silencing complex (RISC).
The table below shows some common and well-studied ncRNAs, but in reality there are 1000’s of
such RNAs in cells and as such the list of ncRNA is increasing with continued new discoveries as the
techniques for detecting them improves. Although the functions of all such RNAs is not fully
understood, what is certain is that some ncRNAs are involved in gene regulation via riboswitches
and gene silencing as well as via metabolite feedback, ribozymatic activities and epigenetics.
Additionally, ncRNAs, in general, are involved in a vast number of processes from DNA replication
(in the form of primer requirements), coding, decoding, code translation, peptide bond formation
and cellular defence against invading mobile genetic elements. This warrants a new postulation that
the overall control of cellular life forms may well reside in a ‘network of RNAs’, whilst the
informational genetic code necessary for life’s perpetuation still rests with DNA – ie the central
dogma of molecular biology (broadly DNAàRNAàProtein) is conserved. Nevertheless these RNA
networks would be passed on from one generation to the next during cell division. It should not go
unnoticed that RNA’s full activity within a cell is masked by an overwhelming presence of a vast
diversity of proteins and the fact that we have not been able to assign a full role to the remaining
non-coding DNAs. To this effect it is now becoming clear that there are no such things as ‘junk’
nucleic acids; everything in the cell has a part to play and is sooner or later utilised.
In this presentation I shall highlight RNA’s influence on life on Earth and suggest how the role of
RNA can be tested in favour of cellular life forms being organised and controlled by RNA/protein.
35 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – ORIGINS OF LIFE | ASB6
Synthetic astrobiology
Lynn Rothschild (invited), NASA Ames Research Center, Brown University, Stanford University,
University of California, Santa Cruz
Synthetic biology – the design and construction of new biological parts and systems and the redesign
of existing ones for useful purposes – has the potential to transform fields from pharmaceuticals to
fuels. Our lab has focused on the potential of synthetic biology to revolutionize all three major parts
of astrobiology: Where do we come from? Where are we going? and Are we alone? For the first
and third, synthetic biology is allowing us to answer whether the evolutionary narrative that has
played out on planet earth is likely to have been unique or universal. For example, in our lab we are
re-evolving the biosynthetic pathways of amino acids in order to understand potential capabilities of
an early organism with a limited repertoire of amino acids and developing techniques for the
recovery of metals from spent electronics on other planetary bodies. In the future synthetic biology
will play an increasing role in human activities both on earth, in fields as diverse as human health and
the industrial production of novel bio-composites. Beyond earth, we will rely increasingly on
biologically-provided life support, as we have throughout our evolutionary history. In order to do
this, the field will build on two of the great contributions of astrobiology: studies of the origin of life
and life in extreme environments.
36 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – ORIGINS OF LIFE | ASB6
Electrochemical assaying of membrane-organic interactions. Potential applications in
astrobiology
T. P. Kee, School of Chemistry, University of Leeds, Leeds LS2 9JT, UK.
Contact: t.p.kee@leeds.ac.uk
Electrochemical studies of lipids on mercury surfaces are fundamental in the determination of the
structure and properties of amphiphilic monolayers. In addition, when such electrode-mounted
membrane monolayers are incubated with organic molecules, interactions between the organic and
membrane can be registered by a change in electrochemical response of the system. This differential
can be parameterised as an electrochemical capacitance modification as a result of phase changes in
the membrane and can inform us further of the type of interaction and how such interactions are
indicative of the chemical class of the interacting molecule.
In this contribution will be presented preliminary studies as to how such electrochemical capacitance
measurements on membrane-organic interactions could be of value in the fields of (i) emergence of
abiotic function and (ii) bio-signature detection.
37 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – ORIGINS OF LIFE | ASB6
Microbial community structure, activity and functionality from six different depths of
deep crystalline bedrock fracture zones from Fennoscandian shield
L. Purkamo1, M. Bomberg1, H. Salavirta1, M. Nuppunen-Puputti1, M. Nyyssönen1, L. Ahonen2, R.
Kietäväinen2, I. Kukkonen2,* and M. Itävaara1
1
VTT Technical Research Centre of Finland Ltd., Espoo, Finland
2
Geological Survey of Finland (GTK), Espoo, Finland
* Current
affiliation: University of Helsinki, Helsinki, Finland
The current surface conditions on Mars are inhospitable for living organisms. The subsurface of Mars
on the other hand can be a potential spot for detecting extraterrestrial life. Groundwater brines are
suggested to support life on Mars, thus research on analogue environments on Earth such as deep,
ancient, oligotrophic and saline bedrock fluids can provide new understanding about existence of
microbes on other celestial bodies (e.g. Fairén et al. 2010, Michalski et al. 2013, Cockell 2014,
Mikucki et al. 2105).
The archaeal and bacterial communities were characterized with high-throughput sequencing, Qiime
and co-occurrence network analysis with Gephi from six bedrock fracture zones from depths of 180
m to 2,3 km in Fennoscandian bedrock. The microbial communities derived from DNA represented
the total community and gene pool available, while communities based on RNA were considered as
a proxy for active populations. Intrinsic bacterial communities differed greatly between the fractures
while archaeal populations were less rich and followed a certain trend, in which hydrogenotrophic
methanogens, such as Methanobacteriaceae were dominating the deeper fractures below 500 m, as
more versatile carbon substrates utilizing methanogens inhabited the shallowest depth studied (180
m). SAGMEG archaea represented the majority of the community in 967 m fracture. Bacteria with
diverse metabolic properties, such as representatives of families Comamonadaceae and
Rhodobacteraceae were dominating the communities in 180 m and 500 m fractures. Bacterial
physiotypes considered mainly lithotrophic were most abundant in 967 m fracture. The abundance
of active bacterial OTUs with unknown physiology was high in depths below 1 km.
The core bacterial community was composed only from seven OTUs found from all DNA-based
communities of the fractures. Most abundant of these were Firmicutes-, Pseudomonas- and
Comamonadaceae-related OTUs. Comamonas was also regarded as a keystone species of the active
bacterial community according to the co-occurrence network analysis. However, the majority of the
OTUs discovered in this study could be regarded as members of the so-called “rare biosphere”,
with their relatively low abundance and uneven distribution throughout the fracture zones. These
also include most of the keystone species identified with the network analysis.
38 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – ORIGINS OF LIFE | ASB6
The Evolutionary Origin of Oxygenic Photosynthesis
John F. Allen, Research Department of Genetics, Evolution and Environment, University College
London, Gower Street, London, WC1E 6BT, U.K.
Contact: j.f.allen@ucl.ac.uk
Hypothesis: The redox switch hypothesis for the first cyanobacterium proposes that the immediate
antecedent of cyanobacteria was an anoxygenic photosynthetic bacterium containing genes for both
type I and type II photochemical reaction centres [1]. These genes were never expressed at the
same time. Instead, they were switched on and off by redox state, permitting growth either with or
without H2S as the electron donor for photosynthesis.
Such a bacterium may have flourished on Earth in the Archean eon, prior to the origin of the
cyanobacteria to which it gave rise. Photosynthetic oxygen evolution then resulted of the
coincidence of two unusual events: (i) failure, by mutation, of the redox genetic switch; (ii)
acquisition of outer-membrane-bound manganese and calcium, with manganese oxidation coupled to
re-reduction of photooxidised chlorophyll [2,3]. These events complemented each other, conferring
a novel and unstoppable selective advantage –– water as the source of electrons for photosynthesis. The reaction product, free molecular oxygen, is inhibitory to carbon and nitrogen fixation.
Oxygen nevertheless became the respiratory electron acceptor of choice for subsequent life. Its
advent drove major transitions of bio- logical and geochemical evolution. The emergence of complex
life depended on the resulting planetary redox disequilibrium.
The proposed protocyano-bacterium (top left) switches between type I and type II reaction centers. If either becomes
permanently switched off, its genes are lost. This process may have given rise to the anoxygenic species Chlorobium and
Heliobacillus (type I), and Chloroflexus and Rhodopseudomonas (type II). A mutation in the redox switch allows the two
photosystems to co- exist. With the Mn4CaO5 catalyst that oxidizes water to oxygen, the two photo-systems become
complementary, and together use light to drive oxygen evolution by the first true cyanobacterium (top right).
39 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – ORIGINS OF LIFE | ASB6
Predictions: 1. The proposed protocyanobacterium, an anoxygenic bacterium with genes for both
type I and type II reaction centers, may have identifiable living descendants [4]. Their modern habitat
is predicted to be: freshwater; anoxic; low light intensity; one with fluctuating concentrations of H2S;
one with a solid substrate for growth of sequential layers of photoautotrophic and
photoheterotrophic cells or biofilms. 2. Stromatolites record alternating modes of metabolism. The
protocyanobacterium may have been the dominant shallow-water primary producer for a billion
years prior the Great Oxidation Event at 2.4 Gyr and have built stromatolites around local sources
of H2S at hydrothermal vents
References: [1] Allen J. F. (2005) FEBS Lett. 579, 963-968. [2] Allen J. F. and Martin W. (2007) Nature 445,
610- 612. [3] Russell M. J. et al. (2008) In: Allen J. F. et al. (eds) Photosynthesis. Proc 14th Intl. Congr.
Photosynth. Springer. pp. 1187–1192. [4] Allen J. F. (2014) In: Golbeck J. H. and van der Est, A. (eds)
Biophysics of Photosynthesis. Biophysics for the Life Sciences, Vol.11, Part V. Springer. pp. 433-450.
40 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – ORIGINS OF LIFE | ASB6
Primary vent structures and graphitic carbon in >3750Ma white smoker type
hydrothermal vent deposits
M.S Dodd and D Papineau
London Centre for Nanotechnology and Department of Earth Sciences, University College London, UK
Almost all Eoarchean sedimentary rocks have undergone medium to high grade metamorphism,
however, small enclaves of Banded Iron Formations (BIFs) and jaspilites from the south-west margin
of the Nuvvuagittuq supracrustal belt (NSB), Canada, are metamorphosed to only upper greenschist
facies; stilpnomelane is prolific as a prograde mineral in some of these rocks, which suggests localised
upper limits of metamorphic conditions only around 430-500 ̊C at 5-6 Kilobars (Miyano & Klein,
1989). Coarsely to finely laminated magnetite+ quartz+ ferrous-silicate BIFs occur along the length
of most of the ca. 3 km long belt and include prograde pyroxene and amphibole and retrograde
phyllosilicates.
The depositional environment discernible in the NSB includes near-vent jaspilites (jasper+
magnetite+ chert+ chalcopyrite± carbonate), which preserve primary diagenetic structures similar to
arrangements in Ordovician jaspers and modern day near-vent hydrothermal Fe-Si deposits (Li et al.,
2012, Peng et al., 2010, Hopkinson et al., 1998), which also include hematite tubes, filaments and
rosettes.
Hematite rosettes occur as concentrically-ringed nanoscopic grains of transluscent martite- hematite
described here in the NSB jaspers. These structures are interpreted to have arisen from
concretionary growth during diagenesis of siliceous-ferrihydrite on the seafloor near the vent,
possibly via Belousov-Zhabotinsky growth process. The diversity and composition of rosettes in the
Ordovician Lokken-Hoydal jaspilites suggests there may be more than only abiogenic diagenesis
responsible for rosette formation in some jaspilites. Hematite tubes and filaments represent a higher
degree of order in the NSB jaspilites than concentric, multilayer rosettes, such tubes and filaments
occur in coarser chert, suggesting a possible connection to metamorphic stretching. The hematite
tubes are unlikely to have a bacterial origin, given the large diameter (25µm) and lack of
diagenetically oxidised or reduced biological materials (graphite/carbonate), which rather point to
abiogenic formation.
In comparison, the nearby localised outcrops of coarse-laminated, limonite-stained carbonate rocks
with chaotic veins of white chert and patches of red chert, are interpreted as a white smoker vent
structure. Micro-Raman analyses of calcite rosettes in these rocks reveal micron-scale graphitic
carbon disseminated throughout the rings and surrounding chert. Raman spectra show a sharp
prominent G- band at 1582cm-1 and a minor D-band at 1342cm-1, consistent with a syngenetic
origin.
The association of graphitic carbon with carbonate rosettes, similar to rosettes suggested to have
formed from carbonic fluids with locally oxidising humic acids in residual fluids (Kohler et al., 2013),
leads to the suggestion that carbonate rosettes formed through the oxidation of organic matter in
iron-rich sediments. Considering average bulk δ13Corg values around -21.9‰ and δ13Ccarb values
between -6.7 and -8.3‰ from these carbonate rocks (Papineau et al., 2011), a likely source of this
hypothetical organic matter might be biogenic organic matter, degraded into humic acids in the
carbonate-siliceous white smoker depositional environment. Alternatively, some non-biological
synthesis of organic matter in vent carbonates could have also originated from hydrothermal fluid
circulation and serpentinisation of the volcanic crust, so future work will focus on the compositions
of these particles of graphitic carbon.
Hopkinson, L., Roberts, S., Herrington, R. & Wilkinson, J. (1998). Geology 26. Kohler, I., Konhauser, K. O., Papineau, D., Bekker, A. &
Kappler, A. (2013). Nat Commun 4, 1741. Li, J., Zhou, H., Peng, X., Wu, Z., Chen, S. & Fang, J. (2012). FEMS Microbiol Ecol 81, 205216. Miyano, T. & Klein, C. (1989). Contributions to mineralology and petrology 102, 478-491. Papineau, D., De Gregorio, B. T., Cody, G.
D., O’Neil, J., Steele, A., Stroud, R. M. & Fogel, M. L. (2011). Nature Geoscience 4, 376-379. Peng, X., Zhou, H., Li, J., Li, J., Chen, S., Yao,
H. & Wu, Z. (2010). Sedimentary Geology 229, 193-206.
41 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – ORIGINS OF LIFE | ASB6
A record of Precambrian hydrothermal vents?
Dominic Papineau
London Centre for Nanotechnology and Department of Earth Sciences, University College London, U.K.
Submarine hydrothermal black smokers on the modern basaltic seafloor have been known since only
the 1970’s to occur at mid-ocean ridges and volcanic seamounts. These vents were deposited as
massive to porous sulphide metal chimneys (Zn, Cu, Fe, Mo, Au, Ag, and As) from volcanicexhalative fluids of acidic and highly reducing compositions. In comparison white smokers are known
to occur in association with serpentinised ultramafic rock (peridotites and gabbros) at slowspreading centers and precipitate from carbonate- and sulphate-rich oxidising and alkaline fluids.
Fluids from white smokers typically are 1) rich in CO2, Ca, SOx, and SiO2; 2) depleted in most
chalcophilic metals (except Cu, Ba, Au, and U), and 3) include dissolved H2 and CH4 from
serpentinised crust. The distinctive chemical composition and mineralogy of these modern
structures thus serves as a guide for finding them in the Precambrian rock record. This is challenging
however, because most Precambrian rocks have been metamorphosed often to the amphibolite
facies and especially those in volcanically and tectonically active settings.
Precambrian Banded Iron Formations (BIFs) tend to occur in kilometer-long outcrops as
narrow bands of coarsely to finely laminated layers interbedded with volcanic rocks. These Fe-rich
layers are dominated by different minerals and therefore old BIF classification schemes have been the
silicate-, sulphide-, oxide- and carbonate- facies BIFs. Here we present a revised classification of BIFs
based on mineralogy, associations with white or black smoker type rocks, and other notable
petrological associations with BIFs from the late Paleoproterozoic circum-Superior basins (Canada
and U.S.A.), the late Paleoproterozoic to Neoarchean of the North China Craton, the Neoarchean
Abitibi-Temiskaming terrane (Canada), the Neoarchean to Paleoproterozoic Dharwar and Aravalli
cratons (India), and the Paleoarchean of Western Australia. A case is made that black and white
smokers occur in variable expressions in many localities from these Precambrian terranes and show
a pattern of associated BIF types.
For example, localised black and white smoker rock types generally appear geographically
separated, although sometimes they occur only meters apart on the same pillowed basaltic oceanic
crust. Most Paleoproterozoic and Archean white smokers tend to be constituted of 1) chaotic
metacarbonate rocks, often silificified with white and/or red chert patches and veins, 2) sparry
calcite chimneys with occasional accretionary lapili, 3) boxwork carbonate, 4) chaotically laminated
coarse-grained limonite-stained carbonate, and 5) injected filamentous-botryoidal gray hematite.
These rocks are typically associated with jaspilite BIFs (jasper+ chert+ magnetite± chalcopyrite)
interbedded with chlorite-rich metavolcanic rocks. Jaspillites are often associated with pillow basalt
that are occasionally serpentinised and with massive basalt fractured by massive white barite or
jasper and metacarbonate veins. We find that these localised metacarbonate rocks are often
associated with jaspilitic BIFs.
In comparison, Paleoproterozoic and Archean black smokers are composed of variable
sulphidic structures. Black smoker chimneys occur as 1) massive pyrite (e.g. VMS), 2) localised
primary marcasite felsic rocks, 3) porous filamentous marcasite tubes coated in goethite, or 4)
localised patches of botryoidal to chaotic goethite+ limonite+ hematite rocks. Most of these
structures occur in association with pillow basalt, black chert, taconite-slaty red-gray hematite BIF,
and carbonaceous shales or metapelites. Interestingly, we also find possible localised vent structures
dominated by massive grey hematite. Iron formations associated with these black smoker structures
include quartz+magnetite+ferrous silicate BIFs and quartz+magnetite+jasper oxide BIFs. Overall
characteristics of Precambrian black and white smokers are thus similar to modern hydrothermal
vents and this work provides a framework to find and document these structures both in the
modern and Precambrian rock record.
42 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – EXOPLANETS | ASB6
Twinkle - a UK mission to understand exoplanet atmospheres
Tessenyi, Marcell (UCL); Tinetti, Giovanna (UCL); Savini, Giorgio (UCL); Tennyson, Jonathan
(UCL) and Twinkle payload + Science consortium.
The study of exoplanets has been incredibly successful over the past 20 years: nearly 2000 planets
have been discovered, and along these discoveries fundamental parameters such as mass, radius and
semi-major axis have been obtained. In the past decade, pioneering results have been obtained using
transit spectroscopy with Hubble, Spitzer and ground-based facilities, which have enabled the
detection of a few of the most abundant chemical species, the presence of clouds, and also
permitted the study of the planetary thermal structure.
Twinkle will be a Made-in-Britain, small, dedicated satellite designed to measure the atmospheric
composition of exoplanets. Twinkle will be built quickly and cheaply (£50M including launch and
operations) and will deliver ground breaking scientific results. The Twinkle satellite will be built in
the UK and launched within 4 years, using an existing platform designed by Surrey Satellite
Technology Ltd and instrumentation built by a consortium of UK institutes.
Twinkle will analyse >100 exoplanets in our galaxy and a few objects in our solar system. Its infrared
spectrograph will enable observations of a wide range of planet types including super-Earths and
hot-Jupiters. Some of the target planets are orbiting stars similar to our Sun and some are orbiting
cooler red-dwarfs. For the largest planets orbiting bright stars, Twinkle will even be able to produce
maps of clouds and temperature. The Twinkle instrument will be composed of a visible-IR
spectrograph (between 0.5 and 5µm) with resolving power R~200, and will orbit Earth on a sunsynchronous polar orbit.
43 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – EXOPLANETS | ASB6
Biosignatures on super-earths with hydrogen-dominated atmospheres.
William Bains1,2, Sara Seager1,3, Renyu Hu4, Andras Zsom1 .
1
Department of Earth, Atmospheric and Planetary Sciences, MIT, 77 Mass. Ave., Cambridge, MA 02139, USA.
Rufus Scientific Ltd., 37 The Moor, Melbourn, Royston, Herts SG8 6ED, UK
3
Department of Physics, MIT, 77 Massachusetts Ave., Cambridge, MA 02139, USA,
4
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91109, USA
2
Background: Planets with masses intermediate between Earth and Neptune that have a defined,
solid surface and a thin atmosphere (“Super-Earths”) are a new class of potentially habitable planet
without precedent in our Solar System, but which have been suggested to be common by recent
exoplanet surveys. It is plausible that such planets will retain or acquire an atmosphere dominated by
hydrogen. We have explored the atmospheric signatures that life might produce on such worlds.
Approach: We have computed the likely production and atmospheric removal rates of the gas
products of energy metabolism, biomass building, and a small sample of secondary metabolite gases
that are made by life on Earth. Gas removal by atmospheric photochemistry was modeled [1]. Both
gas production and gas removal mechanisms are different in an H2-dominated atmosphere from
those on any solar-system Earth-like planet. In solar system planets, gas removal is dominated by
reaction with ×OH and :O radicals, whereas in the H2-dominated atmosphere, removal is usually
dominated by reaction with ×H [3]. The nature of the gas produced depends on the reason that life
produces that gas. Specific calculations therefore depend on whether a gas is made as a result of
energy capture, biomass capture, or for other reasons.
Energy capture reactions: Energy capture reactions in an H2-dominated environment will
produce reduced compounds such as H2S and CH4, which cannot be unambiguously differentiated
from geochemically produced volatiles. An exception is ammonia (NH3), whose production is
exergonic in an H2-dominated world. We show that only a small amount of biomass is needed to
produce detectable NH3 levels [2]. Geochemical production of NH3 is likely to be very slow,
photochemical removal even in an H2-dominated atmosphere will be rapid, and so detection of NH3
in an H2-dominated super-earth atmosphere may be a biosignature.
Photosynthesis: We examined the plausibility of photosynthesis in an H2-dominated environment
[4]. The H2 in an H2-dominated atmosphere is a potent greenhouse gas, allowing liquid water on the
surface of a super-earth orbiting a sun-like star at 10AU. Enough light energy reaches the surface of
such worlds to sup-port photosynthesis; however the most plausible volatile product of
photosynthesis is hydrogen, which can-not be distinguished from atmospheric hydrogen. Ammonia is
also a possible photosynthetic product.
Secondary metabolites: Life on Earth produces a number of gaseous products for reasons other
than energy capture or biomass building, such as CH3Cl. We examined a sample of these other
metabolic products, and identified ones that are plausible candidates for biosignatures on an H2dominated world. Current work is exhaustively enumerating possible secondary metabolite
biosignature volatiles.
Conclusions: A habitable environment is possible on an H2-dominated super-Earth, and such
planets have a wider habitable zone than planets with an oxidized atmosphere like Earth or Mars.
However detecting life on an H2-rich super-Earth may be harder than detecting life on a true Earth
analogue, as its most plausible photosynthetic byproduct will be H2, and many energy capture
reactions will generate gases that cannot be distinguished from those from geochemical sources. We
put forward ammonia as a candidate biosignature gas for an H2-dominated rocky planet. Secondary
metabolite gases may also be detectable biosignatures on such worlds.
References: [1] Hu, R. et al (2012) Astrophysical Journal, 761:166 (29pp) [2] Seager, S. et al (2013) Astrophysical Journal 775: 104
(28pp). [3] Seager et al (2013) Astrophysical Journal 777: 95. [4] Bains, W. et al Life 4: 716-744
44 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – EXOPLANETS | ASB6
Dynamical constraints on multi-planet exoplanetary systems
Jonti Horner1,2, Robert Wittenmyer2,3, Jonathan Marshall2,3 & Tobias Hinse4
1University
of Southern Queensland West St, Toowoomba QLD 4350, Australia
Centre for Astrobiology, UNSW Australia, Sydney, NSW 2052, Australia
3School of Physics, UNSW Australia, Sydney, NSW 2052, Australia
4Korea Astronomy and Space Science Institute, Daejeon 305-348, Korea
2Australian
In recent years, an ever-growing number of planets have been claimed orbiting other stars. The great
majority of these candidate planets are discovered by indirect means – typically by observing the
periodic ‘wobbling’ or ‘winking’ of a potential planet host star.
Here, we present the results of detailed dynamical simulations of several proposed multi-planet
exoplanetary systems. Our simulations, which typically involve over 100,000 individual realisations of
a given system, examine how the planets proposed to orbit therein would interact with one another
on 100 million year timescales.
We have found that such simulations can act as useful ‘sanity check’, revealing candidate planetary
systems where the proposed architecture is dynamically unfeasible. In such cases, our results suggest
that either the best-fit solution for the proposed candidate planets is flawed (which can often be
remedied by the acquisition of further observational data), or that some other explanation must be
sought to explain the observed variability of the planet host star.
For other candidate planetary systems, our results show the proposed architecture to be
dynamically stable. In order words, the proposed planets are certainly feasible. In addition, our
results often reveal that the dynamical limits on the orbits of the planets are significantly stricter than
those obtained purely on the basis of a best-fit to the observed behaviour of the host star.
As such, these dynamical simulations can help us to better characterise the planets we discover, as
well as allowing us to check whether the planets we think we have found are truly all that they seem
to be.
45 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – EXOPLANETS | ASB6
Exomoons: How to find them and why they matter to Astrobiology
David Waltham
Royal Holloway, University of London
Contact: d.waltham@rhul.ac.uk
Moons may play a role in life in the Universe in two distinct ways:
1. A large moon may be important for habitability of its parent planet
2. Large moons themselves, may be important habitats
The most plausible effect that moons have on habitability is through their effect on axial stability. I
will show that the question of whether large moons stabilize or destabilize a planet’s spin axis
depends upon how strongly moon-size is correlated with planetary spin rate. If systems with large
moons also tend to spin fast then large-moons enhance stability but, if initial spin-rate is independent
of moon-size, then small-mooned systems will tend to be more stable. Unfortunately, the strength
of this correlation is unknown and existing computer models of the moon-forming collision do not
offer any clues. Characterization of a significant sample of exomoons would resolve this issue.
As well as aiding habitability, moons may themselves form two distinct types of plausible habitats.
Tidally heated icy-moons may be the most common habitats in the Universe (there are 9 moons like
this in the solar system alone). In addition, Earth-sized moons orbiting “warm-Jupiters” are a
plausible form of habitable world. Characterizing moons orbiting gas-giant exoplanets will allow us
to determine the frequency of these potentially habitable kinds of world.
The first detection of exomoons is likely to result from analysis of transit time variations (TTVs).
TTVs are produced because orbital rotation of the planet-moon system, around its common centre
of gravity, cyclically enhances and retards the timing of planet transit. However, TTVs are also
generated by the perturbing influence of other worlds in the system and so an observed TTV signal
is not necessarily the consequence of an orbiting moon. Furthermore, the TTV signals produced by
moons and by inferior planets are necessarily undersampled and the resulting “aliasing” complicates
analysis. In this presentation I will illustrate these issues using a new analysis of data from Kepler 30
and also indicate how they may be resolved.
Finally, I will briefly discuss Twinkle; a UK-led mission to characterize the atmospheres of
exoplanets. This low-Earth-orbit, cheap, fast mission should produce data of sufficient precision to
allow detection of exomoons. The UK may find the first extra-solar moon and we could do so by
2019.
46 | ORAL ABSTRACTS – THU 3 SEP, AFTERNOON – EXOPLANETS | ASB6
The structure of the ‘Asteroid-belt’ analogue around HR8799
Jonti Horner1,2, Bruna Contro2,3, Robert Wittenmyer2,3 & Jonathan Marshall2,3
1University
of Southern Queensland West St, Toowoomba QLD 4350, Australia
Centre for Astrobiology, UNSW Australia, Sydney, NSW 2052, Australia
3School of Physics, UNSW Australia, Sydney, NSW 2052, Australia
2Australian
The planetary system discovered orbiting the star HR8799 is, in many ways, one of the closest
analogues found to date of our own Solar system – albeit both significantly younger and on a larger
scale. The system features four giant planets, directly imaged over the past decade, organised in an
architecture strikingly similar to that exhibited by our own giant planets.
In addition, observations of the HR8799 system at infrared wavelengths have revealed the presence
of two debris disks. The first, exterior to the orbit of HR8799 b (the outermost planet in the
system) is analogous to the Solar system’s Edgeworth-Kuiper belt, and was directly imaged by the
Spitzer Space Telescope. The second debris disk lies interior to the orbit of HR8799 e (the
innermost planet found to date), and is analogous to the Solar system’s asteroid belt.
Whilst the extent of HR8799’s outer debris disk has been relatively constrained by the direct images
obtained by the Herschel and Spitzer Space Telescopes, the innermost disk is known purely as a
result of the excess radiation observed at infrared wavelengths from HR8799 itself. Since the disk is
far closer to its host star, it cannot yet be directly resolved, and we most instead rely on indirect
methods to determine its structure and radial extent.
Here, we present the results of a detailed dynamical investigation of the HR8799’s inner debris disk.
We have followed the dynamical evolution of a million massless test particles, distributed interior to
the orbit of HR8799 e, which has allowed us to map the likely extent and structure of this Asteroid
belt analogue. As is the case in our Solar system, we find that the disk likely exhibits a large amount
of internal structure – extra-solar “Kirkwood Gaps”.
In addition, our results reveal that objects in the theoretical ‘habitable zone’ of HR8799 would be
dynamically stable on timescales comparable to the system’s age – which leaves open the possibility
that the system may one day be found to be an even better analogue for our own Solar system than
is currently thought!
47 | ORAL ABSTRACTS – FRI 4 SEP, MORNING – HABITABILITY | ASB6
Uninhabited habitats
Charles S Cockell (invited)
School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3FD
Planetary environments can be placed into one of three categories: 1) uninhabitable, 2) inhabited
habitat, 3) uninhabited habitat. The search for life on other planets usually makes the assumption that
where there is a habitable environment, it will contain life. This is because on the present-day Earth,
the third category, uninhabited habitats, are rare. Experiments using artificial endoliths demonstrate
that within one month under typical winter temperate environmental conditions uninhabited habitats
can become completely inhabited. On present-day Earth, they may occur naturally in pockets of
subsurface oils or impact craters that have been thermally sterilized in the past. Beyond the Earth,
uninhabited habitats may be more common. They might exist on inhabited planets, similarly to the
Earth, and they might also exist on uninhabited planets, for example on a planet that is habitable, but
where life never originated. The hypothesis that uninhabited habitats are abundant is experimentally
testable by studying other planets. On ancient Mars, uninhabited habitats may have existed in
environments such as transient impact-generated or volcanic hydrothermal systems. On more
recent Mars, uninhabited habitats might have been created in places such as melted subsurface
permafrost or regions of surface glacial melting during periods of changing obliquity. The possibility
that some habitable Martian environments were uninhabited has important consequences for which
habitable environments should be the highest priority for robotic and human exploration. The study
of uninhabited habitats might ultimately inform an understanding of how biology has influenced
geochemistry on the Earth.
References
Cockell CS (2011) Vacant habitats in the Universe. Trends Ecol. Evolution, 26, 73-80
Cockell CS (2014) Trajectories of Martian habitability. Astrobiology 14, 182-203.
48 | ORAL ABSTRACTS – FRI 4 SEP, MORNING – HABITABILITY | ASB6
The Carbonate-Silicate Cycle on Habitable Exoplanets: Implications for Long-term
Habitability
Andrew J. Rushby, Centre for Ocean & Atmospheric Science, University of East Anglia
The length of a planet’s ‘habitable period’ is an important controlling factor on the evolution of life
and of intelligent observers. Planets discovered in orbit around other stars in the galaxy will have
habitable periods of different lengths relative to the Earth. Furthermore, complex states of
habitability derived from complex interactions between multiple factors (e.g. temperature, availability
of carbon, redox balance) exist over the course of the evolution of an individual terrestrial planet
with implications for long-term habitability and biosignature detection. The duration of these
habitable conditions are controlled by multiple factors, including the orbital distance of the planet, its
mass, the evolution of the host star, and the operation of (bio)geochemical cycles on these
exoplanets.
A zero-D biogeochemical box model was formulated to investigate the operation of the carbonatesilicate cycle under conditions of varying incident stellar flux (for stars from 0.2 to 1.2 M⊙), from a
stellar evolution model developed by Rushby et al. (2013), and planet size (from 0.5 to 10 M⊕) to
compute the duration of habitable conditions as a function of these parameters.
Figure 1: Output from a zero-D carbon-cycle model designed to investigate the biogeochemical evolu- tion of terrestrial
planets in the habitable zone of their stars.
The concept of ’habitability’ can be explored in multi-parameter space, specifically in regards to
temperature and atmospheric carbon availability for (C3) photosynthesis (>150 ppm pCO2). A
detailed sensitivity analysis revealed a statistically significant relationship between planet mass and the
length of habitable conditions, suggesting that planetary factors that scale with mass (primarily
geothermal heat flux) have a non-linear effect on the carbonate-silicate cycle and its ability to buffer
planetary climate.
49 | ORAL ABSTRACTS – FRI 4 SEP, MORNING – HABITABILITY | ASB6
Snowball Earth & the struggle to maintain habitability: lessons for exoplanets
Indranil Banik, Scottish Universities Physics Alliance, University of St Andrews, North Haugh, Fife,
St Andrews, KY16 9SS
Contact: ib45@st-andrews.ac.uk
In the ongoing quest to better understand where life may exist elsewhere in the Universe, important
lessons may be gained from our own planet. In particular, I will explain what can be learned from
planetary glaciation events that Earth suffered ∼600 million years ago, the so-called ‘Snowball Earth’
episodes.
First, I will introduce a toy radiative balance model that gives a basic idea of how the climate works.
This will help to explain how the ice-albedo feedback effect can destabilise the climate of a planet.
The process relies on lower temperatures causing more ice to form. Ice being very reflective, the
climate is cooled further, leading to yet more ice.
This instability rarely causes a runaway planetary glaciation because of an important stabilising
mechanism − the carbonate- silicate cycle, or weathering feedback.1 Lower temperatures lead to less
rainfall and weathering of surface rocks, reducing the rate at which carbon dioxide (CO2) is
removed from the atmosphere. Continued emission from volcanism leads to its atmospheric levels
building up, enhancing the greenhouse effect. This shows the necessity of geologic activity on a
habitable world.
Next, I will review some of the evidence that Earth really did suffer a planetary glaciation, and most
likely several. I will explain the probable reason that the usual stabilising mechanism failed, and why
that is (fortunately) very rare. Unfortunately, if it does occur, it appears to be extremely difficult to
break out of, both in reality and in my toy model (Figure 1).
Interestingly, the Cambrian explosion occurred soon after a series of Snowball Earth episodes. Thus,
although these events have an adverse effect on life in the short run, the long term effects are less
clear.
Most stars are smaller and fainter than the Sun, making their respective habitable zones closer in. As
a result, tidal effects may well cause planets in these regions to be tidally locked to their parent stars.
In the context of my toy model, I will discuss how runaway planetary glaciations on such planets
would compare with similar events on Earth. The aspect I will emphasise is that radiation from
fainter stars tends to be mostly at near-infrared wavelengths. Here, ice is less reflective than in the
visible.2 This makes the ice-albedo feedback less powerful and thus planetary glaciations less likely. If
one did still occur, deglaciation should be easier than on Earth, assuming atmospheric collapse is
avoided.
If there is time, I will discuss how the Snowball Earth hypothesis has affected our understanding of
what limits the extent of the habitable zone at its outer edge. Very acidic conditions in Earth’s
oceans during its Snowball phases3 suggest that some unlucky exoplanets.
50 | ORAL ABSTRACTS – FRI 4 SEP, MORNING – HABITABILITY | ASB6
Figure 1: A planetary glaciation event in my toy model. Left: Rates of radiation absorbed and emitted by an Earth analogue as a function of
◦
the ice-open water transition latitude θI. The planet can be at the stable solution near θI = 60 , making it much like Earth today. The
◦
greenhouse climate forcing factor g = 1.5 (this just scales the ‘absorbed’ curve). Middle: If g were reduced to 1.29, θI would drop to 38 in
equilibrium. However, even very slightly lower values of g lead to a runaway planetary glaciation. In this situation, the planet settles at the
solution θI = 0. Note that the ‘absorbed’ curve intersects the vertical portion of the ‘emitted’ curve, indicating an Equatorial temperature
◦
◦
≪ 0 C. Right: This is how it remains, unless more radiation is absorbed than that required to maintain a temperature of 0 C at the
Equator (1 in these units). This only occurs if g ≥ 3.62, this being 180% more than at the glaciation threshold. Defrosting the Earth is
difficult. However, the corresponding result for a planet orbiting an M dwarf is ∼24% (not shown), as ∼3 times more of any incident
radiation is absorbed by ice than on Earth.
References: 1Walker, J. C. G., Hays, P. B., Kasting, J. F. in Journal of Geophysical Research, C10, 9776−9782
(1981) 2Joshi, M. M. & Haberle, R. M. in Astrobiology, 12, 1, 3−8 (2012) 3Kaseman, S. A., Prave, A. R., Fallick,
A. E., Hawkesworth, C. J., Hoffman, K-H. in Geology, 38, 9, 775−778 (2010)
51 | ORAL ABSTRACTS – FRI 4 SEP, MORNING – HABITABILITY | ASB6
The Influence of Jupiter and Mars on Earth’s orbital evolution
Jonti Horner1,2, James Gilmore2 & Dave Waltham3
1University
of Southern Queensland West St, Toowoomba QLD 4350, Australia
Centre for Astrobiology, UNSW Australia, Sydney, NSW 2052, Australia
3Department of Earth Sciences, Royal Holloway, University of London
2Australian
In the coming years, it is likely that the first potentially Earth-like planets will be discovered orbiting
other stars. Once found, the characterisation of those planets will play a vital role in determining
which will be chosen as the first targets for the search for life beyond the Solar system. As such, we
must be able to gauge the relative importance of the various factors proposed to influence potential
planetary habitability, in order to best focus that search. One of the plethora of factors to be
considered in that process is the climatic variability of the exoEarths in question.
In our Solar system, the Earth’s long-term climate is driven by several factors – including the
modifying influence of life on our atmosphere, and the temporal evolution of Solar luminosity. The
gravitational influence of the other planets in our Solar system add an extra complication – driving
the Milankovitch cycles that are thought to have caused the on-going series of glacial and interglacial
periods that have dominated Earth’s climate for the past few million years.
In this talk, we present the results of two suites of integrations that together examine the influence
that the architecture of our Solar system has on the Earth’s Milankovitch cycles. We consider
separately the influence of the planets Jupiter and Mars, both of whom contribute to the forcing of
Earth’s orbital evolution on timescales of tens of thousands and hundreds of thousands of years.
Our results illustrate how small changes to the architecture of a given planetary system can result in
marked changes in the potential habitability of the planets therein, and are an important first step in
developing a means by which the nature of climate variability on planets beyond our Solar system
can be characterised.
52 | ORAL ABSTRACTS – FRI 4 SEP, MORNING – ISS/HSF | ASB6
The BIOMEX and BIOSIGN experiments on the ISS – two missions in low Earth Orbit
supporting future space missions for the search for life on Mars and the icy moons
Jean-Pierre de Vera (invited)
German Aerospace Center (DLR), Institute of Planetary Research, Rutherfordstr. 2, 12489 Berlin,
Germany
Contact: jean-pierre.devera@dlr.de
One of the main challenges in astrobiology and planetary research in the near future is to realize
space missions to study the habitability of Mars and the icy moons of the Jovian and Saturnian
system. Mars is an interesting object to search for fossilized life because of its past water driven wet
history. River beds, sedimentary deposits indicating the presence of lakes [1] as well as a supposed
but highly debated presence of a former ocean on the north hemisphere [2] are clearly showing that
the atmosphere must have been much denser and the conditions much more habitable than
nowadays. Even today still water activity is present in specific niches on the surface of Mars [3]. This
leads to the conclusion that the search for habitable environments on Mars and the presence of biotraces of extinct or extant life is a reasonable enterprise to be conducted in the next space missions.
Besides the planet Mars other planetary objects in our solar system are promising candidates to find
life as there are the icy moons. The Jovian moon Europa is one promising candidate, where water
driven resurfacing activity of its icy crust must regularly happen because of the low amount of impact
craters on the surface as well as the clear observations of cryo-volcanos which can only be explained
by the presence of a liquid water ocean beneath the surface. Fissures and cracks with colored salty
deposits coming from the inner side of the supposed global ocean are also clearly showing that this
ocean can be a habitable environment [4] and where it would be good to search for present life. The
Saturnian moon Enceladus seems also to be a promising candidate to search for life. On this moon
high water plumes come out of an ocean covered by its ice crust [5]. Some observations by the
probe of Cassini also have shown that besides the presence of water and salt a high number of
simple and complex organics was observed within these plumes. Also for the Saturnian moon Titan
an ocean is supposed beneath the icy crust and this moon has not to be neglected in future
astrobiology-driven exploration missions. Because of these very important observations of the last
decades international and interdisciplinary scientific teams are working on new types of space
missions with the main task to search for life. To realize these space missions, the scientific teams of
the ESA-experiments BIOMEX and proposed BIOSIGN are combining work performed in planetary
analog field sites with work in the lab and analysis performed in planetary simulation facilities as well
as combined with research in space on specific exposure facilities as there are satellites and the
International Space Station (ISS). The technology developments and scientific approaches gained by
this specific combined work try to solve problems which might occur if we would like to detect life
on the other planets and moons in our solar system. For that, technology is used and tested in
planetary analog environments like in the deep sea as well as in dry and cold deserts and different life
detectors are tested, developed and used during these field campaigns before testing them in space
and using further in the next space exploration missions to Mars and the icy moons.
[1] Goldspiel J.M. and Squyres S.W. (1991), Ancient aqueous sedimentation on Mars, Icarus, 89 (2), 392-410.
[2] Di Achille G. and Hynek B.M. (2010), Ancient ocean on Mars supported by global distribution of deltas and
val-leys, Nature Geoscience, 3, 459 – 463.
[3] McEwen A.S. et al. (2011), Seasonal Flows on Warm Martian Slopes. Science 333 (6043), 740-743.
[4] Crawford G.D. (1988). Gas-driven water volcanism and the resurfacing of Europa. Icarus, 73 (1), 66–79.
[5] Hunter Waite J. et al. (2006), Cassini Ion and Neutral Mass Spectrometer: Enceladus Plume Composition
and Structure, Science, 311 (5766), 1419-1422.
53 | ORAL ABSTRACTS – FRI 4 SEP, MORNING – ISS/HSF | ASB6
Principia, the International Space Station and the ELIPS programme
Charlotte Blake-Kerry, UK Space Agency
In light of the forthcoming mission of Tim Peake, the UK Space Agency will survey nascent UK space
environments research and human space exploration.
Following initial government investment in 2012, and renewed commitments in 2014, the UK is an
established partner in the European Space Agency’s (ESA) programmes for human spaceflight and
microgravity research. Building on this, in July 2015 a National Strategy for Space Environments and
Human Spaceflight was published, to provide a framework for this diverse work in the UK,
identifying key actors and setting out government priorities. Reflecting the strength of the UK
astrobiology community, it is one of four highlighted research areas in the new Strategy.
Research on the International Space Station (ISS) and space-analogue facilities, such as drop towers,
parabolic flights and Antarctic stations, represents the breadth of the sciences (and even some
arts). Astrobiology, with its foundational interdisciplinarity, is perhaps uniquely positioned to benefit
from these extreme research platforms.
This will be visibly demonstrated in December 2015, as Tim Peake becomes the first British ESA
astronaut to visit the ISS. During his six month mission, named ‘Principia’ after Sir Isaac Newton’s
famous text, he will carry out experiments in fields including medicine, physics, materials science and
– of course – astrobiology.
54 | ORAL ABSTRACTS – FRI 4 SEP, MORNING – ISS/HSF | ASB6
Automatic Prediction of Fatigue from Speech Recordings: Human Space Flight
technology for Earth application
Mark Huckvale, Psychology and Language Sciences, UCL
Khan Baykaner, Psychology and Language Sciences, UCL
Iya Whiteley, Centre for Space Medicine, Mullard Space Science Laboratory, UCL
Oleg Ryumin, Gagarin Cosmonaut Training Centre
Svetlana Andreeva, Gagarin Cosmonaut Training Centre
Introduction: Operator fatigue is a significant risk factor in aerospace. A variety of methods exist
which claim to detect or estimate fatigue. Some of these are accurate but based on physiological
measurements requiring expensive or intrusive equipment. Since in many aerospace environments
operators are engaged in regular verbal communication, a fatigue estimation method based on the
analysis of speech might provide a cheaper and less intrusive alternative.
Method: In an ESA-funded study seven speakers took part in an isolation experiment in which they
were awake for over 60 hours. Speech recordings were made every 6 hours on average. A set of
1093 acoustic features were calculated from each recording describing statistical properties related
to signal variability in the frequency domain, the temporal domain and the modulation domain.
Samples were labelled as fatigued/not-fatigued based on the time spent awake.
Results: A binary classification system using a support-vector machine showed good discrimination
between the fatigued/not-fatigued classes, with 80% unweighted accuracy using speaker-independent
features, and 90% with speaker-dependent features. All measures were collected using a leave-oneout cross-validation scheme.
Discussion: Results are promising for applications in the Low-Earth-Orbit and exploration human
space flights, real-world Earth based domains, where operators are in regular verbal communication
as part of their normal working activities.
Keywords: Fatigue, Speech, Machine Learning, Human Space Flight 55 | ORAL ABSTRACTS – FRI 4 SEP, MORNING – ISS/HSF | ASB6
NemaFlex: A microfluidic tool for phenotyping (neuro)muscular strength in spaceflown C. elegans
Mizanur Rahman1, Jennifer Hewitt1, Frank Van Bussel2, Jerzy Blawzdziewicz2, Monica Driscoll3,
Nathaniel Szewczyk4, Siva A Vanapalli1
1Department
of Chemical Engineering, Texas Tech University.
Engineering, Texas Tech University.
3Department of Molecular Biology and Biochemistry, Rutgers University.
4MRC/Arthritis Research UK Centre for Musculoskeletal Ageing Research, University of
Nottingham, UK.
2Mechanical
A major impediment to long-duration space travel is loss of muscle mass and strength during
spaceflight. Surprisingly, the small 959-celled nematode Caenorhabditis elegans is a good, cost-effective
model for studying the effects of spaceflight upon muscle—much muscle biology is conserved from
nematode to human. Our past experiments on ISS have shown that the expression of key muscle
genes that encode members of a muscle attachment complex is reduced in C. elegans during space
flight. A key open question is if and how these changes in gene expression result in reduced muscle
strength in response to spaceflight. While reduced force production is documented for astronauts, it
is yet to be demonstrated for C. elegans. To address this critical knowledge gap, we developed a
miniaturized device, the NemaFlex, which enables measurement of worm strength. The NemaFlex
contains a microfluidic chamber containing hanging pillars that are deflected as the nematode crawls
through them. We find that animals subjected to muscle contractions with an acetylcholine agonist,
prior to paralysis show the same maximum strength as the untreated animals suggesting NemaFlex
quantitates maximum strength. We test mutants with neuronal defects (unc-17 and unc-119) and
impaired sarcomeres (unc-52 and unc-112) and observe changes indicating the neuromuscular origin
of strength. Finally, we will discuss our work plan to adapt our NemaFlex device for flight definition
studies involving measurement of worm strength across multiple generations.
56 | ORAL ABSTRACTS – FRI 4 SEP, MORNING – ISS/HSF | ASB6
The human exploration of space - confronting old and new chemical risks to health
Dr John R Cain
GeoFind Consultancy, Hookstone Chase, Harrogate, North Yorkshire
This paper will review the known chemical health hazards associated with living and working in space
in particular on board the ISS and following the colonisation of the Moon and Mars. Extraterrestrially, it is highly likely that astronauts will be exposed to new chemical hazards with the
associated health effects. The sources of the new chemical hazards for example, from the use of 3D
printing (e.g. Nanoparticles), from asteroid and planetary mining (e.g. rare metal dusts), from life
support systems (e.g. PAHs) and from the use of synthetic biology (e.g. arsenic compounds) will be
discussed. This will be followed by a discussion on how exposomes can be used to identify new
chemical hazards and on how the measurement of biomarkers and Space Maximum Allowable
Concentrations (SMACs) can be used to assess the chemical exposure health risks. In conclusion,
the paper will examine how an assessment of the health risks can be used to determine the
measures to mitigate exposure during space flight.
Keywords: chemical hazards, exposomes, biomarkers, Space Maximum Allowable Concentrations, risk
assessment, mitigation
57 | ORAL ABSTRACTS – FRI 4 SEP, MORNING – ISS/HSF | ASB6
Establishing molecular mechanisms of and countermeasures to muscle decline in space
Etheridge T1, Szewczyk NJ2.
1College
of Life and Environmental Sciences, University of Exeter, St. Luke’s Campus, Exeter, EX1
2LU, UK.
2Division
of Medical Sciences and Graduate Entry Medicine, University of Nottingham, Royal Derby
Hospital, Derby, DE22 3DT, UK.
Loss of muscle mass is one of the most pronounced and consistent adaptations to spaceflight. The
rate of this exponential muscular decline, if left unabated, is sufficient to reduce ambulation on
return to Earth, impair in-flight operations and potentially threaten astronaut health. Previous flight
experiments have repeatedly demonstrated altered gene expression. For example, reduced
expression of components of insulin-mediated metabolism have been reported in several species
including humans, as have lowered expression of mechanically sensitive muscle attachment
complexes. On Earth these same alterations produce smaller and weaker muscles. Whether these
molecular responses are causal of muscle decline in flight and if targeting these systems can
counteract such changes remains unknown. We have established the nematode Caenorhabditis
elegans as a model organism that recapitulates the molecular adaptations to spaceflight observed in
humans. Our recently selected flight experiment will, therefore, employ C. elegans to target
components of the insulin- and attachment-mediated intramuscular signalling cascades onboard the
International Space Station. Specifically, muscle-specific DAF-2/Insulin receptor overexpression, daf16/FOXO mutants and DAF-16::GFP transgenic animals will determine the role of the most
proximal and distal components of the insulin signalling cascade in spaceflight-induced muscle decline.
Flying dim-1 mutants and wild-type animals cultured with calpain protease inhibitors will establish
whether known methods for preventing attachment-mediated muscle loss on Earth are effective
during spaceflight. Post-flight frozen animals will be analysed versus flown wild-type and matched
ground controls, for DAF-16::GFP nuclear translocation (indicative of transcriptional activation),
transcriptomic and proteomic profiling, targeted molecular analyses, immunofluorescent markers of
muscle structural status, and D2O stable isotope / GC-pyrolysis-IRMS assessment of protein, lipid
and DNA synthesis as indices of muscle health. In doing so, this project will establish: i) whether loss
of insulin signalling and/or muscle attachment is causally linked with muscle defects during spaceflight
and, ii) whether targeting these molecular systems prevents muscle decline in flight. These
experiments will provide the first definitive demonstration of mechanisms underlying muscle loss in
space, and facilitate future targeted therapeutic development.
58 | ORAL ABSTRACTS – FRI 4 SEP, AFTERNOON – ISS/HSF | ASB6
Impact studies in the laboratory concerning survival of fossils hypothetically launched
toward the moon
Burchell M.J.1, Yolland L.2 Price M.C.1, McDermott K.M.1
Centre for Astrophysics and Planetary Sciences, School of Physical Science, Ingram Building,
University of Kent, Canterbury, Kent Ct2 7NH, UK.
1
Computational Life and Medical Sciences Network, University College London, 20 Gordon Street,
London WC1H.
2
Contact: m.j.burchell@kent.ac.uk
It has previously been hypothesized that ejecta from giant impacts on the Earth might contain fossils.
These ejecta could impact the Moon, and potentially transfer terrestrial fossils to the Moon (see
[1]). In a previous paper we tested this hypothesis by firing at water targets diatom fossils frozen
into projectiles (see [2]). In that work the impact speeds ranged from 0.4 to 5.3 km s-1,
corresponding to peak shock pressures in the range 0.2 to 19 GPa. We found examples of intact
diatoms at all speeds, but the incidence of intact survival fell heavily at the higher speeds, as did the
mean size of the diatoms.
In this present work we show a new method for firing diatoms. We no longer freeze the diatoms
into ice to fire them. Instead, we use a nylon sabot with a hollow central shaft (approximately 3 mm
deep with a diameter of 3 mm). Diatom fossils suspended in water were placed into the central shaft
which was then sealed with a rubber cap glued into the recessed top of the sabot. The loaded sabot
was then fired in a two stage light gas gun [3] into a target of water in similar fashion to the previous
work [2].
Two shots were performed in the new work, at impact speeds of 2.05 and 2.10 km s-1. We
extracted the diatoms as before [2] and will show examples in the talk. The Planar Impact
Approximation [4] is used to calculate the peak shock pressure for a water sample impacting water.
We compare the resulting peak pressure to that found for illustrative Earth rocks (e.g. sandstone)
which impact the Moon with typical speeds estimated by [5].
We have thus demonstrated a new capability for the Kent light gas gun of firing at speeds of a few
km s-1 materials suspended in liquid solution onto targets. This method should also work at higher
speeds. The results here confirm our previous work showing that fossils can survive impacts at
speeds similar to those of terrestrial rock’s impacting the Moon.
References
[1] Armstrong JC et al. 2002. Rummaging through Earth’s attic for remains of ancient life. Icarus 160, 183–196.
[2] Burchell MJ et al. 2014. Survival of fossils under extreme shocks induced by hypervelocity impacts. Phil.
Trans. R. Soc. A 2014 372, 20130190. Free to download form
http://rsta.royalsocietypublishing.org/content/372/2023/20130190.
[3] Burchell MJ et al. 1999. Hypervelocity impact studies using the 2MV Van de Graaff dust accelerator and
two stage light gas gun of the University of Kent at Canterbury. Meas. Sci. Tech. 10, 41–50.
[4] Melosh HJ. 1989 Impact cratering: a geologic process. Oxford, UK: Oxford University Press.
[5] Armstrong JC. 2010 Distribution of impact locations and velocities of earth meteorites on the moon. Earth
Moon Planets 107, 43–54
59 | ORAL ABSTRACTS – FRI 4 SEP, AFTERNOON – ISS/HSF | ASB6
The Astrobiological Case for Human Space Exploration
Ian Crawford
Department of Earth and Planetary Sciences, Birkbeck College London, Malet Street, London, WC1E
7HX.
Contact: i.crawford@bbk.ac.uk
An ambitious programme of human space exploration, such as envisaged by the Global Exploration
Strategy, will help advance the core aims of astrobiology in multiple ways. In particular, a human
exploration programme will confer significant benefits in the following areas: (i) the exploitation of
the lunar geological record to elucidate conditions on the early Earth; (ii) the detailed study of Near
Earth Objects for clues relating to the formation of the Solar System; (iii) the search for evidence of
past and/or present life on Mars; (iv) the provision of a heavy-lift launch capacity which will facilitate
the exploration of the outer Solar System; and (v) the construction and maintenance of sophisticated
space-based astronomical tools for the study of extrasolar planetary systems. In all these areas a
human presence in space, and especially on planetary surfaces, will yield a net scientific benefit over
what can plausibly be achieved by autonomous robotic systems. A number of policy implications
follow from these conclusions, which are also briefly considered.
60 | ORAL ABSTRACTS – FRI 4 SEP, AFTERNOON – SETI | ASB6
The UK SETI Research Network
Alan Penny (invited)
University of St Andrews, UK
The UK SETI Research Network (UKSRN) was set up in 2013 with the purpose of promoting
academic work on SETI in the UK. It is open to people who are members of UK universities or of
UK learned institutions and who have published on SETI. At present (early 2015) it has 25 members.
As part of its work it has held two annual 2-day meetings, with a third planned for September 2015.
The members have varied interests, ranging from the analysis of search techniques, the nature of ET
civilisations, to the sociology of SETI. Lists of the papers given in the first two meetings is available
on the UKSRN website.
The use of the Network will be discussed, together with prospects of any UK SETI search. In
particular, the possibility of co-operation with SETI researchers in other European countries, and its
relation to the IAASETI.
The UKSRN has a website http://www.seti.ac.uk.
61 | ORAL ABSTRACTS – FRI 4 SEP, AFTERNOON – SETI | ASB6
What can we know about life on other worlds?
Dr William Edmondson
Honorary Senior Research Fellow, School of Computer Science, University of Birmingham
Contact: w.h.edmondson@cs.bham.ac.uk
There are several ways to answer this question. One approach is to look at terrestrial biochemistry
and explore through laboratory work “possible life” chemistries, and consequently possible
biologies. This work involves considering possible evolutionary pathways and events. There are
difficulties: we don’t really understand how life developed on the planet we inhabit and although we
know about existing bio-chemistry we are unsure how both chemistry and life changed and evolved
in combination over the rather long times we suppose to have been involved. Another approach is
to set aside that phase of evolution, and work instead with the emergence of differentiated life forms
through evolution from some arbitrarily chosen starting point. The point of this line of work is to
answer questions about the inevitability or otherwise of the emergence of intelligent life in some
sort of recognizable form. Both approaches look increasingly interesting to astronomers because
they can be developed to yield predictions about detectable “life signatures” of one sort or another.
The spectral analysis of light from HR8799c, using OSIRIS and the Keck telescope, shows where this
might go if the work can be done with smaller planets in the Goldilocks zone around a star close
enough to permit our imaging technologies to work. Of course, this is a constantly changing
scenario as the laboratory models develop and the imaging hardware likewise.
There is a third approach – more directly focussed on the Search for Extra-Terrestrial Intelligence.
Here the argument is that ETI, as such beings are called, will communicate the fact of their existence
– in one way or another, perhaps intentionally, perhaps not. The argument is that we can learn
something of life on other worlds by being informed directly about it by ETI. This is the stuff of
Science Fiction as well as more conventional SETI meetings – with debates on messaging, image
transmission, radio leakage, etc. The work does concern astronomers in the sense that the imaging
equipment (radio and optical) has to be developed, refined, deployed and so forth. This third
approach can be argued to provoke developments in more conventional astronomical techniques, as
indeed can be argued for any approach which prompts the definition of a plausible “life signature”.
In this case the “life signature” is a signal.
However – there is a fourth approach which only indirectly leads to proposals for “life signatures”.
It focuses on the issue of intelligence rather directly, but in a novel way. The argument is built on
the exploration of a functional analysis of the brain. The question to be answered becomes “What is
the functional specification of the brain?” and the subsidiary question is “How might intelligence
produce a unique life signature?”. If we can say something about brains in all species on earth and
can extend that understanding to all brains anywhere, including the brains of ETI, then we can
conjecture about a different sort of “life signature” which could be sought. It can be argued that all
brains, anywhere, at any time (and irrespective of wetware) have to conform to the Sequential
Imperative. We can thus know quite a bit about non-terrestrial organisms with brains. What we
need to work through is the possible inevitability of intelligence. It can further be argued from
understanding of semiotics that ETI will be content to observe what it considers to be ETI (e.g.
humans on Earth). “Life signatures” reduce to visibility of artefacts and habitation, with the
commensurate requirement for humongous optical telescopes. The presented paper will develop
these arguments.
62 | ORAL ABSTRACTS – FRI 4 SEP, AFTERNOON – SETI | ASB6
Engaging a search for non-terrestrial artefacts on the moon
L. J. Pinault1, and I. A. Crawford1, 1The Centre for Planetary Sciences at UCL/ Birkbeck
Contact: l.pinault@ucl.ac.uk
Introduction: With the discovery of a first ‘Earth 2.0’ candidate amongst thousands of exoplanets
and an infusion of step-changing funds for ‘Breakthrough Listen’ and ‘Breakthrough Message’
research by Internet entrepreneur Yuri Milner, the stage is set for a renaissance in SETI endeavours
[1]. In parallel, the authors have suggested advances in the application of computer vision, machine
learning, and nanotechnology that portend a new phase in the search for non-terrestrial artefacts,
specifically within the comparatively backyard confines of the Earth-Moon system [2]. Using citizen
scientists’ selections and identifications based on Moon Zoo Lunar Reconnaissance Orbiter (LRO)
images algorithms are trained to begin automatically distinguishing Earth spacecraft hardware from
boulders, craters and other lunar morphologies. At the micron and sub-micron scale, methods are
developed for identifying manufactured particles in lunar regolith simulant and amongst fines from
the Lunar Sample Laboratory.
The Search for Non-Terrestrial Artefacts – Background: Published contributions regarding
the search for non-terrestrial artefacts in our own solar system include the works of Viewing [3],
Papagiannis [4], Stephenson [5], Arkhipov [6,7], Crawford [8,9], Rose and Wright [10], and Davies
and Wagner [11]. Arkhipov established the feasibility of intra-galactic transport of micron/
submicron particles of manufactured matter from other technological civilisations – their minute
asteroid mining tailings, burned-away chemical rocket components, etc. Davies and Wagner
proposed the application of Moon Zoo’s crowdsourcing capabilities [11] to detect evidence of alien
probes or past alien activities and operations on the Moon. Our work [2] builds on each: firstly, by
suggesting that, in light of Earth’s own nanotechnology advances, Arkhipov particles might
conceivably be programmable and designed to self-assemble into devices when encountering natural
raw materials as found on the Moon; these would be the ultimate in cheap mass-produced Bracewell
probes [13], and potentially be detectable at LRO/ Moon Zoo levels of image resolution. Secondly,
even if Arkhipov particles reaching the Moon are mere incidental alien trash, and not programmed
to self-assemble, our own fast-emerging nanotechnologies may be able to detect even their finest
traces in the lunar regolith at molecular scale.
Computer Vision and Machine Learning Applied to Moon Zoo: We have taken the
coordinates of ‘spacecraft hardware’ and ‘other’ identifications from some of the highest-resolution
(0.4m to 0.5m) images so far presented to users on the citizen science Moon Zoo platform, where
known Apollo artefacts are visible to the trained eye, and overlaid them using ArcGIS mapping onto
corresponding co-projected best-quality LROC images. By coupling a Haar Features Cascade
Classifier with OpenCV [14,15], we are able to train the distinction between positive (Earth
spacecraft hardware) and negative (boulders, shadows, other natural phenomenon) samples.
Nanotechnology to Detect Arkhipov Particles: We are developing various mechanical,
magnetic and other sifting approaches to search for manufactured particles in lunar regolith
simulants. Some of the more promising rely on some of the very technologies that may have been
used in the making of Arkhipov particles. New methods have now been developed at UCL/Imperial
College London Centre for Nanotechnology to pick out a single target molecule of pollutant,
explosive, or illegal drug from 1018 water molecules within milliseconds, by trapping it on a selfassembling single layer of gold nanoparticles. The systems are comparatively cheap and portable,
and are now being trialled for field use [16].
The authors are advancing a model to estimate the possible flux of Arkhipov particles as a function
of the number of past technological civilisations in our galaxy, to approximate the concentration of
non-terrestrial artefacts on the Moon, and constrain the number of such civilisations if no such
particles are found.
References: [1] Overbye D. (2015, July 21) Russian Entrepreneur Pledges Millions to Alien Search New York Times, A12. [2] Pinault L. and
Crawford I. els2015.arc.nasa.gov. [3] Viewing D. (1975) J. Brit. Interplanet. Soc. 28, 735. [4] Papagiannis M. (1978) QJRAS 19, 277. [5]
Stephenson D. (1979) QJRAS 20, 422. [6] Arkhipov A. V. (1996) Observatory, 116, 175-176. [7] Arkhipov A. V. (1998) J. Brit. Interplanet.
Soc. 51, 181-184. [8] Crawford I. A. (2000) Scientific American 283(1), 38-40. [9] Crawford I. A. (2006) Int. J. Astrobiology 5(3), 191-197. [10]
Rose C. and Wright G. (2004) Nature 431 47-49. [11] Davies P. C. W. And Wagner R. V. (2013) Acta Astronaut. 89, 261 265. [12] Joy K.H.
et al. (2011) Astron. Geophys. 52(2), 2.10-2.12.[13] Bracewell R. N. (1960) Nature 186 (4726) 670-671. [14] see http://en.wikipedia.org/
wiki/OpenCV [15] Reinus S. (2013) Dept. Inf. Technology Upsala Univ. Sweden. [16] Cecchini M. P. et al. (2012) Nature Matls. 12, 165- 171.
63 | ORAL ABSTRACTS – FRI 4 SEP, AFTERNOON – SETI | ASB6
Astrobiology and the legal definition of life
Mukesh Bhatt [doctoral student]
School of Law, Birkbeck College
Contact: m.bhatt@physics.org
The growing use of evidence-based science in legal judgments over the last few decades attempts to
provide a clearer statement of what life is by using information and definitions provided by the
scientific disciplines. The newer and constraining definitions of life as provided by astrobiology and in
particular the RNA-World models are likely to have a clear impact on the way legal and ethical
decisions are made. Law does not appear to have a consistent or coherent, indeed formal definition
of life. Legal systems across the world apply a "working model' of life to determine decisions
applicable to specific cases. These are often drawn from general principles based on experience,
religion and philosophy; the law appears to defines life by "we know it when we see it". This is to
compared with the use of approaches from astrobiology, earlier approaches by Schrodinger,
Lovelock and others; of the long-held and evolving taxonomic categories; information from the
genome project, perspectives from artificial life, synthetic life, artificial life and the cognitive sciences.
A formal legal definition of life derived from astrobiology would affect many areas of human activity:
gene patents, abortion, the right to life debate, environmental protection with respect to non-human
organisms and the protection of potentiality for evolutionary niches in space and on Earth for the
future; a survey of these issues in relation to law and the legal definition is now necessary given
recent scientific advances.
Keywords: law, astrobiology, definition of life, legal judgement,
64 | POSTER ABSTRACTS | ASB6
POSTER ABSTRACTS
(alphabetical by surname)
Are reduction spheroids signatures of microbial life?
Connor Brollya,, John Parnella & Stephen Bowdena
aDepartment
of Geology & Petroleum Geology, University of Aberdeen, Aberdeen, UK
Reduction spheroids are the most commonly encountered morphology of reduction in the
geological record. Their formation is somewhat debated but the evidence observed favors a
microbial formation mechanism. The spherical morphology indicates they were not formed at the
surface during deposition, but at depth, after compaction. Reduction spheroids are commonly found
with dark metal rich cores which include U, V, Se, Mo & Cu (1,2). Theses metals have been shown
to be reduced by certain strains of iron reducing bacteria, which are thought to be responsible for
the majority of reduction in iron rich environments (2). It was originally thought that carbon was the
reductant which created the spheroid; however this was largely based on assumption, due to the
dark colouration of the cores (3). The majority of reduction around detrital organic material tends
to be lensoidal, indicating reduction took place at an early stage of compaction. Additionally
calculations by previous authors show that the amount of carbon commonly found within a
reduction spot, was not sufficient to reduce the surrounding volume of sediment (4,5). A reductant
which is catalytically sustained and chemically inert is required, which again favors a microbial
method (5). Experimental work aims to replicate the formation of reduction spheroid by culturing
iron reducing bacteria, Geobacter bemidjiensis, in an iron rich substrate to prove that reduction
spheroids are undoubtedly a microbial feature. They could be used as life signature on Earth but
could equally be applied to the search for life on Mars, given the volume of iron in the Martian
sediments.
References
1: Coates JD et al. Appl Environ Microbiol. 1996;62:1531–6. 2: Lovley D. FEMS Microbiol Rev. 1997;20:305–13.
3: Hofmann BA. Society for Geology Applied to Mineral Deposits Special Publication. 1993; 362–78. 4:
Hartmann M. Geochim Cosmochim Acta. 1963;27:439–99. 5: Hofmann BA. Chem Geol. 1990;81:55–81.
65 | POSTER ABSTRACTS | ASB6
Ionic strength is a barrier to the habitability of Mars
Mark G. Fox-Powell1, Claire R. Cousins2, John E. Hallsworth3 & Charles S. Cockell1
1UK
Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Mayfield Road,
Edinburgh, UK EH9 3JZ; 2Dept. Earth and Environmental Sciences, University of St. Andrews, Irvine Building,
St. Andrews, UK. ; 3Institute for Global Food Security, School of Biological Sciences, MBC, Queen’s University
Belfast, Belfast, UK BT9 7BL
Contact: m.fox-powell@ed.ac.uk
A considerable body of evidence indicates the existence of hypersaline surface waters throughout
the history of Mars. It is therefore assumed that, as on Earth, the thermodynamic availability of
water (water activity) is a crucial limiting factor for martian habitability. However, differing geologic
histories can drive planetary-scale variations in aqueous chemistry, with as-yet-unknown implications
for habitability. As products of different geochemical processes from their terrestrial counterparts,
martian brines exhibit unique combinations of stressors not normally encountered in brine
environments on the Earth. By studying microbial colonization of simulated martian brines, we show
that high ionic strength in martian waters constrains their habitability to a smaller window than is
predicted by current paradigms. We demonstrate experimentally that ionic strength, driven to
extremes on Mars via enrichment of divalent ions such as Mg2+, Fe2/3+ and SO42-, acts to render
environments uninhabitable, even when water activity is deemed permissive. Currently, even worsecase assessments for martian brine habitability are based solely on water activity and thus may not
be conservative enough. As the chemical composition of a planet’s water bodies is directly
dependent on its geologic evolution, these results provide a case study for how differing planetaryscale geochemistries can drive differential habitability on two neighbouring rocky planets. Planets
that follow a Mars-like trajectory during their surface evolution are likely to present previously
unrecognised but nevertheless significant challenges to biology. Ionic strength, a hitherto overlooked
barrier to life, may define habitability at both a microbial and planetary scale.
66 | POSTER ABSTRACTS | ASB6
The Small Planetary Linear Impulse Tool, SPLIT, A New Approach to Rock Sampling
John Holt1, Mark Sims1, Helen Atkinson2, Mike Lovell3
1 Space
Research Centre, University of Leicester
of Engineering, University of Leicester
3 Dept of Geology, University of Leicester
2 Dept
One of the major problems facing remote robotic in-situ missions is ambiguity caused by the nature
and characteristics of the measurement surface which may mask an underlying, more representative
mineralogy, petrology or hidden bio-signature (We use the term bio-signature broadly here to
include isotopic, molecular and morphological indicators).
The Small Planetary Linear Impulse Tool, SPLIT, has the principal aim of facilitating targeted deep
access to the interior of rocks for non-contact and/or contact analysis, and subsequent sampling on a
hostile planetary surface. SPLIT is a sample facilitator and should be seen in the context of a remote
robotic arm end effector; it is a small, unique low power technique, intended to be used either in
isolation or complementary to other surface preparation tools enabling targeted sampling with a
suite of scientific instruments, depending on mission objectives, and offers three clear advantages.
• It does not damage the structure and chemical distribution of the sample
• Depth of the weathering rind can easily be determined
• Contamination from the tip is mitigated or removed completely presenting a largely flat dust
free pristine surface
If life exists or has ever existed on Mars it will have sought refuge inside the rocks. SPLIT enables
scientists to open a rock like a book and read its ancient secrets, increasing our understanding of the
origin, evolution, distribution and future of life in the Universe.
67 | POSTER ABSTRACTS | ASB6
Astrobiology at the University of Southern Queensland
Jonti Horner1,2, Carolyn Brown1, Brad Carter1, Rhodes Hart1, Stephen Marsden1, Matthew
Mengel1, Belinda Nicholson1, Jack Soutter1 & Ian Waite1
1University
2Australian
of Southern Queensland West St, Toowoomba QLD 4350, Australia
Centre for Astrobiology, UNSW Australia, Sydney, NSW 2052, Australia
Research at the University of Southern Queensland (USQ) in Australia is focused on the study of
stellar astronomy and planetary systems, and is motivated by the search for habitable planets beyond
the Solar system.
Our research projects include radial velocity searches for habitable-zone exoplanets (as part of the
Anglo-Australian Planet Search program, AAPS), the study of how the space weather exuded by
planet-hosting stars impacts upon their planetary systems (the STARWINDS project), and a variety
of dynamical studies of the stability and habitability of exoplanetary systems (using the n-body
dynamics package, MERCURY). In addition, USQ’s astronomical observatory, located at Mt. Kent, is
regularly used in the follow-up of exoplanet transit search work (as part of the broader Kilodegree
Extremely Little Telescope, KELT, program), and stands as a dedicated southern-hemisphere facility
that can observe transiting planets across most of the night sky.
Each of these research projects are being used to support a USQ research theme that aims to
understand the factors influencing planetary habitability as the star and its planetary system evolve
over time, and this poster will highlight the exciting new results coming out of these different
streams of astrobiological research.
68 | POSTER ABSTRACTS | ASB6
The Instability of the 2:1 Mean Motion Resonance of Neptune
Jeremy Wood1,2, Jonti Horner2,3, Tobias Hinse4
1Hazard
Community and Technical College 1 Community College Drive Hazard, Ky USA 41701
of Southern Queensland West St, Toowoomba QLD 4350, Australia
3Australian Centre for Astrobiology, UNSW Australia, Sydney, NSW 2052, Australia
4Korea Astronomy and Space Science Institute, Daejeon 305-348, Korea
2University
The average time that Centaurs display libration-like behavior in the 2:1 mean motion resonance of
Neptune (at ~18.94 AU) is determined by a mixed methods approach. 8,022 massless test particles
initially starting in the vicinity of the 2:1 mean motion resonance of Neptune are integrated for 3
Myr while in elliptical orbits subject to the perturbing gravitational forces of a motionless Sun and
the Jovian planets Jupiter, Saturn, Uranus, and Neptune. The RMVS method of integration in the
SWIFT software package is used.
The initial inclinations of test particles are chosen randomly from a range of 0 to 40 degrees, and
initial eccentricities are randomly chosen from a range of 0 to 0.7. Graphs showing the evolution of
semi-major axis vs. time for a block of test particles are first qualitatively examined to determine the
maximum amplitude of the osculating and average semi-major axis during libration. We then use a
bespoke code to determine the average libration time for all test particles that librate for more than
10 kyr consecutively while the average and osculating semi-major axes remain within the bounds of
the resonance.
The diffusion of the semi-major axes of the test particles over time is observed. The time test
particles spend within different small body populations (such as the Centaurs, Jupiter Family comets,
etc.) is determined. We pay particular attention to the common dynamical pathways taken by
Centaurs to the inner solar system. The study of such pathways is of particular astrobiological
interest since ancient Centaurs were a likely source of Earth’s water through collisions with Earth
eons ago. Furthermore, the Centaurs continue to contribute to the impact flux at Earth, acting as
the direct source of the short-period comet population. Finally, we present case studies of
interesting test particles that illustrate the various dynamical pathways that can be followed by the
Centaurs.
69 | POSTER ABSTRACTS | ASB6
2001 QR322 – an update on Neptune’s first unstable Trojan companion
Jonti Horner1,2, Patryk Sofia Lykawka3
1University
of Southern Queensland West St, Toowoomba QLD 4350, Australia
Centre for Astrobiology, UNSW Australia, Sydney, NSW 2052, Australia
3Astronomy Group, Faculty of Social and Natural Sciences, Kinki University, Shinkamikosaka 228-3,
Higashiosaka-shi, Osaka, 577-0813
2Australian
The Neptune Trojans are the most recent addition to the panoply of Solar system body populations.
The orbit of the first discovered member, 2001 QR322, was investigated shortly after its discovery,
based on early observations of the object, and it was found to be dynamically stable on timescales
comparable to the age of the Solar system.
As more observations accrued of the object, the best orbital solution available changed, and in 2010
we examined the dynamical stability of the new orbit for the object. In that work, we found that
2001 QR322 lay on the boundary between a highly dynamically stable part of Neptune’s Trojan cloud,
and a much less stable region. Overall, we found that our population of ‘clones’ of 2001 QR322
decayed over time, with a dynamical halflife of ~553 Myr. Our study highlighted the need for further
observations of the object to be carried to refine its orbit, to attempt to disentangle the truth of its
dynamical stability.
Here, we provide an update, five years on from our initial study. We have carried out fresh
dynamical simulations of the evolution of a swarm of 351,135 test particles, centered on a new bestfit solution for the objects orbit. The swarm of clones was spread across a range of orbital element
space spanning ±3σ around the best-fit solution, and represents a twenty-fold increase on the
number of test particles considered in our earlier work.
Despite the improved precision with which the orbit of 2001 QR322 is now known, as a result of an
increased observational arc, our results remain the same. The object is still tentatively balanced on
the brink between areas of dramatically different orbital stability – and it seems likely that significant
further observations will be required in order to fully disentangle its true nature.
Despite the continued uncertainty on the true instability of this object, our results reinforce our
earlier conclusions that the Neptune Trojans likely represent a parent population for the Solar
system’s Centaurs. These objects, in turn, are well established as being the proximate parent
population of the Jupiter-family comets, the source of a significant component of the Earth’s ongoing
impact flux. As a result, the Neptune Trojans may well have contributed to the Earth’s past impact
history, playing a role in both the hydration of our planet and occasional collisional mass extinctions.
70 | POSTER ABSTRACTS | ASB6
The Kilodegree Extremely Little Telescope (KELT): Searching for Transiting
Exoplanets in the Northern and Southern Sky
Joshua Pepper1,2, Jack Soutter3, Jonti Horner3,4, Rhodes Hart3, and the KELT Science Team
1Department
of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235, USA
of Physics, Lehigh University, Bethlehem, PA 18015, USA
3University of Southern Queensland West St, Toowoomba QLD 4350, Australia
4Australian Centre for Astrobiology, UNSW Australia, Sydney, NSW 2052, Australia
2Department
The Kilodegree Extremely Little Telescope (KELT) is a ground-based program designed to search
for transiting exoplanets orbiting relatively bright stars. To achieve this, the KELT Science Team
operates two planet search facilities – KELT-North, at Winer Observatory, Arizona, and KELTSouth, at the South African Astronomical Observatory. The telescopes used at these observatories
have particularly wide fields of view, allowing the KELT surveys to study the largest possible number
of potential exoplanet host stars.
The great benefit of targeting bright stars with an exoplanet transit survey is that any planets found
can then be followed up using other astronomical facilities, allowing their accurate characterisation.
This typically involves two steps. The first is confirmation follow-up, where the existence of a planet
is verified using other facilities, and typically takes place before the existence of the planet is widely
publicised.
Once this is achieved, the true benefit of the host star being bright comes into play – with a bright
host, a plethora of additional characterisation observations are possible. These enable us to study
the physical nature of the planet in more detail, as well as helping us to better understand its orbit
and past history.
To this end, the KELT Science Team are working with a large number of other ground-based
facilities, including the Mt. Kent Observatory at the University of Southern Queensland, to achieve
rapid follow-up of any candidate planets. This widely distributed approach is already yielding great
results, with several planet discoveries already published and confirmed.
In this poster, we present a broad overview of the KELT survey and follow-up work, and highlight
some of the most exciting results obtained to date. KELT is a shining example of the value of
international collaboration for the rapid detection and dissemination of exoplanet discovery results.
71 | POSTER ABSTRACTS | ASB6
BCool and the space weather of exoplanetary systems
Stephen Marsden1, Pascal Petit2,3, Sandra Jeffers4, Aline Vidotto5, Julien Morin6, Brad Carter1, Belinda
Nicholson1, Jonti Horner1,7 and the BCool Science Team
1University
2Institut
of Southern Queensland West St, Toowoomba QLD 4350, Australia
de Recherche en Astrophysique et Planétologie, Université de Toulouse, F-31400 Toulouse,
France
3CNRS, Institut de Recherche en Astrophysique et Planétologie, 14 Avenue Edouard, Belin, F-31400
Toulouse, France
4Institut für Astrophysik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, D-37077
Göttingen, Germany
5Observatoire de Genève, Université de Genève, Chemin des Maillettes 51, Versoix, CH-1290,
Switzerland
6Université de Montpellier, Place Eugène Bataillon, CC 072, 34095 Montpellier cedex 05, France
7Australian Centre for Astrobiology, UNSW Australia, Sydney, NSW 2052, Australia
The BCool project is an international collaboration aimed at studying the activity of low-mass stars
from pre-main sequence through to evolved objects. As part of the BCool project over 200 solartype stars, chosen mainly from exoplanet search databases, have been observed using
spectropolarimetry. From these observations surface magnetic fields have been detected on around
40% of the sample with around 20 of these targets having their surface magnetic field topology
mapped, including some with several years of observations so that magnetic cycles can be studied.
One of the main objectives of the BCool project is to use these surface magnetic field maps to
characterise the “space weather” that potential exoplanetary systems may experience. In this poster
we outline the BCool project and its discoveries so far, with an emphasis on how “space weather”
can impact the habitability of exoplanets.
72 | POSTER ABSTRACTS | ASB6
An Estimate of the Total DNA in the Biosphere
Hanna K. E. Landenmark, Duncan H. Forgan*, Charles S. Cockell
United Kingdom Centre for Astrobiology, School of Physics and Astronomy, University of
Edinburgh, Edinburgh, United Kingdom
*Current
address: School of Physics & Astronomy, Physical Science Building, North Haugh, St
Andrews, United Kingdom
Modern whole-organism genome analysis, in combination with biomass estimates, allows us to
estimate a lower bound on the total information content in the biosphere: 5.3 × 1031 (±3.6 × 1031)
megabases (Mb) of DNA. Given conservative estimates regarding DNA transcription rates, this
information content suggests biosphere processing speeds exceeding yottaNOPS values
(1024 Nucleotide Operations Per Second). Although prokaryotes evolved at least 3 billion years
before plants and animals, we find that the information content of prokaryotes is similar to plants
and animals at the present day. This information-based approach offers a new way to quantify
anthropogenic and natural processes in the biosphere and its information diversity over time.
73 | POSTER ABSTRACTS | ASB6
Analysis of high throughput electrochemical detection of molecular signatures based on
membrane disruption behavior
Higor Mendonça De Jesus, University of Leeds
The analysis of compounds known to be indigenous to meteorites are of great value in our being
able to understand the pool of molecular species available from which life could have emerged.
Together with being able to detect and differentiate potential molecular markers of extint and extant
life, the development of careening techniques and technology to assay such bio-signatures is a
significant field of endeavour. Here we present our preliminary, bench-marking studies in this field
using the principle of membrane disruption and electrochemical capacitance measurements to assay
organics from extraterrestrial sources.
74 | POSTER ABSTRACTS | ASB6
Isolation of radiation resistant bacteria from Mars-analogue Antarctic Dry Valleys by
pre-selection
Michaela Musilova1, Gary Wright2, John M. Ward3 and Lewis R. Dartnell4,5
1
Department of Earth Sciences, University College London, London, UK
2
Department of Engineering and Applied Science, Cranfield University, Shrivenham, Swindon, UK
3
Department of Biochemical Engineering, University College London, London, UK
4
UCL Institute for Origins, University College London, London, UK
The Centre for Planetary Sciences at UCL/Birkbeck, Earth Sciences, University College London,
London, UK
5
Extreme radiation resistant microorganisms can survive doses of ionising radiation far greater than
are present in the natural environment. Radiation resistance is believed to be an incidental
adaptation to desiccation resistance, as both hazards cause similar cellular damage. Desert soils are,
therefore, promising targets to prospect for new radiation resistant strains. This is the first study to
isolate radiation resistant microbes using gamma–ray exposure pre-selection from the extreme cold
desert of the Antarctic Dry Valleys (a Martian surface analogue). Halomonads, identified by 16S
rRNA gene sequencing, were the most numerous survivors of the highest irradiation exposures.
They were studied here for the first time for both their desiccation and irradiation survival
characteristics. In addition, the association between desiccation and radiation resistance has not
been investigated quantitatively before for a broad diversity of microorganisms. Thus, a meta-analysis
of scientific literature was conducted to gather a larger dataset. A strong correlation was found
between desiccation and radiation resistance, indicating that an increase in the desiccation resistance
of five days corresponds to an increase in the room temperature irradiation survival of 1 kGy.
Irradiation at -79°C (representative of average Martian surface temperatures) increases the
microbial radiation resistance nine-fold. Consequently, the survival of the cold, desiccation and
radiation resistant organisms isolated here has implications for the potential habitability of Mars for
dormant or cryopreserved life.
75 | POSTER ABSTRACTS | ASB6
Habitability and preservation of biomarkers in Martian analogues in Chile
Philippe Nauny, School of Geographical & Earth Sciences, University of Glasgow
The ExoMars rover (launch planned in 2018) will be the first to carry a drill able to collect samples
as deep as 2 m from the Martian subsurface. These samples are to be later analysed by an on-board
exobiology laboratory to investigate for the presence of biosignatures of present or past life on
Mars.
The presence of liquid water is a key requirement for life as we know it. Geological evidences
suggest that liquid water was present on the surface of Mars in the past and we know that water ice
is still present in the Martian subsurface. Moreover, recent evidence suggests that occasional shortlived episodes of liquid water occur on the Martian surface today. While this liquid water may
support life, the surface of the Martian regolith experiences extreme conditions (intense solar
irradiation, cold temperatures, extreme thermal fluctuations, unstable liquid water). It is
hypothesised that if an Earth-like type of life ever appeared on Mars, it was able to shelter
underground when the surface conditions became deleterious.
The purpose of this work is to study an environment on Earth that experiences similar conditions as
on Mars. The volcano Sairecabur in Chile has been chosen for that purpose and compared with the
nearby Atacama desert, dryest place in the world and used since the 1970s as a Martian analogue by
NASA. Soil samples were recently collected (May 2015) on the volcano between ~4300 and ~5300
m and in the desert (~2400 m).
It is postulated that, at high altitude, most of the microbiota will be found underground, just above
the subsurface ice layer, where liquid water is available. For this reason, a high-resolution depthanalysis of the soil was planned and samples were collected every 2 cm down to 21 cm deep. The
samples are currently analysed for their DNA and organic biomarker contents. A deeper genomic
analysis of the microbiota will later be done by next-generation sequencing and a physico-chemical
analysis of the soils is also planned.
76 | POSTER ABSTRACTS | ASB6
Microbial community diversity in East Antarctic gypsum deposits
Alex Price, University College London
During the 2011/12 GEA-II expedition to East Antarctica, large aggregates of crystalline gypsum
were discovered on the south-facing side of blue ice moraines in the Sør Rondane Mountains. The
aggregates were up to 1m2 in diameter and apparently grew in situ as a result of blue ice sublimation
on the moraine gravel surface. Preliminary sulphate sulphur and oxygen isotope data revealed
variation within samples, but all with a positive corellation between the oxygen and sulphur isotopes
and most with distinctly higher sulphur isotope values than in modern seawater. The variation may
reflect stages of bacterial sulphate reduction (Jacobs et al., 2012). Several isolates have been cultured
from the sediment at the base of the aggregates and that which is trapped in the uppermost layers.
DNA sequencing will provide more information as to the true composition of the community.
77 | POSTER ABSTRACTS | ASB6
The DeepHotMicrobe Project - crowd funding as a tool for communicating science and
enhancing public engagement
L. Purkamo & M. Bomberg
VTT Technical Research Centre of Finland Ltd., Espoo, Finland
The DeepHotMicrobe project aims to determine the limits of life in ultra deep terrestrial crystalline
bedrock and to describe the environmental factors restricting the existence of microbial life at these
depths. How deep can we go and still find active microbial life in the fracture fluids of crystalline
bedrock? Are there isolated microbial communities that have adapted to the slow hot life of their
living habitats and furthermore, have these followed a unique evolutionary path? Our project is part
of a large scientific effort to characterize the biological and physicochemical environment of a 6-7 km
deep hole that will be drilled in Otaniemi, Espoo, Finland during 2015-2016 for geothermal heat
production by the energy company St1 Deep Heat. The Otaniemi drill hole will reach twice as deep
as the current limit of detected microbial life in the terrestrial realm. The ambient temperature
estimates are around 100-120°C at 6-7 km depth, and the fluids in the isolated bedrock fractures are
assumed to be highly saline and ancient.
Besides the scientific interest, this project has a strong emphasis on science communication to the
public. Part of the funding for the project will be retrieved with a crowd funding campaign that
involves popularization of science. The crowd funding campaign will be launched at August 2015 in
the mesenaatti.sci webpage. The first perk for pledgers is a monthly newsletter about the progress
of the project. The second perk is a ticket to a Coffee-n’-Cake -event where the public can meet us
scientists for informal discussion about the project and science behind it. The third and the most
expensive perk will be purchasing a small piece of rock from a specific depth including a description
of the rock type, the ambient temperature and other environmental characteristics of that depth.
Overall, this project will be actively promoted in social media, such as Facebook and Twitter
(#deephotmicrobe).
78 | POSTER ABSTRACTS | ASB6
Investigating preservation of molecular signatures of life in a unique Mars analogue in
the arid high-altitude Chilean Altiplano
Thomas, N.*, Couto, J., Nauny, P., Porteous, R., Sloan, W., Toney, J., Phoenix, V.
*University
College London
The question of whether life has ever existed on Mars has long fascinated the scientific community
and general public alike, as is evidenced by the amount of robotic missions sent to the red planet in
recent history. Of course, such robotic missions are difficult and expensive, and it is with this in
mind that terrestrial Mars Analogue regions are used.
This study utilises a novel analogue region in the high Chilean Altiplano, encompassing numerous
high altitude (>5000m) sites. The region features low temperatures, high aridity and exceptionally
high solar flux which heats the soil surface. A suite of environmental recordings were taken at each
site, and soil samples were collected over a range of depths from the surface down to 40cm. The
collected soils are to be examined for recoverable genomic content as well as presence of lipidderived Biomarkers and raman-detectable organics. Preliminary investigations indicate reduced
genomic content at the soil surface, suggesting that organic material is better preserved in the
shallow subsurface.
Work is ongoing, DNA recovered from soils has been used in production of a 16S clone library
which was Sanger sequenced. Extracts are in the process of being prepared for Illumina 16S
amplicon sequencing in the immediate future to enable phylogenetic analysis of the microbial
community of this extreme environment.
79 | POSTER ABSTRACTS | ASB6
Subsurface Halophiles: An Analogue for Potential Life on Mars.
P.F Woolman1, V.K. Pearson1, C.S. Cockell2 and K. Olsson-Francis1
1Open
2
University, Milton Keynes, United Kingdom
University of Edinburgh, Edinburgh, United Kingdom
The present day martian surface is cold, dry, exposed to UV radiation and bombarded with heavy
ions [1]. Any remaining water in the near subsurface is likely to have a high salt concentration
because of the likely evaporative processes occurring in those environments. Halophiles are UV
resistant [3] and have an ability to entomb themselves within salt crystals during periods of
desiccation [4], halophiles have therefore been proposed as analogues for potential martian life.
Boulby Salt and Potash Mine in Yorkshire has excavations up to 1.4 km underground and is the
second deepest mine in Europe. Despite this depth and the darkness, Norton et al., [5] isolated
halophiles from the halite deposits. In this project, we will attempt to isolate and characterize
halophiles from halite and other salt-rich sediments from Boulby Mine such as potash, sylvinite,
anhydrite and polyhalite, in order to gain an understanding of potential life in the subsurface of Mars.
Although the Boulby Mine is used as a martian analogue environment [6], it does possess certain key
differences from modern Mars, in particular its aerobic environment and warm temperature. Our
long-term goals, once we have characterized the micro-organisms present, are to expose them to
Mars conditions (past and present) to determine their ability to grow in such environments.
Elements of the martian environment being considered include variations in temperature, lack of
oxygen and variations in brine composition. , We will then focus on defining molecular biomarkers
and geochemical bio-signatures that may be used as evidence of past or present life on Mars.
[1] [1] Mahaffy, P., et al., Science, 2014. [2] Sawyer, D.J., et al., Meteoritics & Planetary Science, 2000. 35(4): p.
743-747 [2] Fischer, E., et al. (2014). Geophysical Research Letters 41(13) [3] Landis, G.A., Astrobiology, 2001.
1(2): p. 161-4 [4] Grant, W. D., R. T. Gemmell and T. J. McGenity (1998). Halophiles. Extremophiles: Microbial
Life in Extreme Environments. K. Horikoshi and W. D. Grant, [5] Norton, C.F., T.J. McGenity, and W.D.
Grant, Journal of General Microbiology, 1993. 139(5): p. 1077-1081. [6] Cockell, C.S., et al., 2013. 54(2): p.
2.25-2.27.