Marsbugs: The Electronic Astrobiology Newsletter
Volume 11, Number 15, 6 April 2004
Editor/Publisher: David J. Thomas, Ph.D., Science Division, Lyon College, Batesville,
Arkansas 72503-2317, USA. dthomas@lyon.edu
Marsbugs is published on a weekly to monthly basis as warranted by the number of articles and announcements. Copyright of this compilation exists with the editor,
except for specific articles, in which instance copyright exists with the author/authors. Opinions expressed in this newsletter are those of the authors, and are not
necessarily endorsed by the editor or by Lyon College. E-mail subscriptions are free, and may be obtained by contacting the editor. Information concerning the scope
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Articles and News
Page 1
Page 2
Page 2
HUNT FOR EXTRASOLAR EARTH-LIKE PLANETS
INTENSIFIES
Royal Astronomical Society press notice PN04-14
MOON-TO-MARS FEASIBLE, EXPERTS SAY, BUT
POLITICS, LACK OF INDUSTRY COOPERATION COULD
JEOPARDIZE VISION
By Leonard David
CAN INTELLIGENT LIFE THRIVE IN CLOSE
QUARTERS? AN INTERVIEW WITH CHRISTOPHER
CHYBA
By Henry Bortman
Page 8
SPACE DEFINES MARS SAMPLE RETURN MISSION
EADS Astrium press release
Page 8
CHEAP COMMUNICATION SCHEMES FOR ET
By Seth Shostak
Page 8
ASHES OF THE PHOENIX
By Peter Backus
Page 9
EUROPA: LIVING WORLD OR FROZEN WASTELAND?
AN INTERVIEW WITH CHRISTOPHER CHYBA
By Henry Bortman
Announcements
Page 10
Page 3
LIFE BENEATH THE ICE IN THE OUTER SOLAR
SYSTEM?
Royal Astronomical Society press notice PN04-10
NEW ADDITIONS TO THE ASTROBIOLOGY INDEX
By David J. Thomas
Mission Reports
Page 4
TITAN'S LAPPING OIL WAVES
Based on a Royal Astronomical Society report
Page 11
CASSINI SIGNIFICANT EVENTS
NASA/JPL release
Page 5
HUMAN EXPLORATION OF THE MOON AND MARS
Royal Astronomical Society press notice PN04-09
Page 12
MARS EXPLORATION ROVERS STATUS REPORTS
NASA/JPL releases
Page 5
METHANE DETECTION POINTS TO LIFE ON MARS
By Robert Zubrin
Page 14
MARS EXPRESS: COMMISSIONING ALMOST
COMPLETE
ESA release
Page 6
MOLECULAR MIDWIVES HOLD CLUES TO THE
ORIGIN OF LIFE
From SpaceDaily
Page 14
MARS GLOBAL SURVEYOR IMAGES
NASA/JPL/MSSS release
Page 7
PLANETARY SYSTEMS WITH HABITABLE EARTHS?
Royal Astronomical Society press notice PN04-13
HUNT FOR EXTRASOLAR EARTH-LIKE PLANETS INTENSIFIES
Royal Astronomical Society press notice PN04-14
23 March 2004
An international group of astronomers led by Dr. Jean-Philippe Beaulieu
(Institut d'Astrophysique de Paris) and Dr. Martin Dominik (University of St.
Andrews) are about to continue their hunt for extrasolar planets with an
enhanced world-wide telescope network in May this year. They are hoping to
secure the firm evidence for the existence of Earth-mass planets orbiting stars
other than the Sun, which has so far eluded astronomers. Dr. Dominik will
describe the project, known as PLANET (Probing Lensing Anomalies
NETwork), at the Royal Astronomical Society National Astronomy Meeting
at the Open University on Thursday 1 April.
Recent scientific research shows that the existence of life on other worlds is a
realistic scenario. By measuring the periodic variation of the radial velocity
of stars induced by an orbiting planet, astronomers have so far detected over
100 planets but all of them are large, similar to Jupiter and Saturn in our solar
system, and environmental conditions suitable for life do not exist on such gas
giant planets.
The only technique currently capable of detecting planets similar to Earth
makes use of the phenomenon called "galactic microlensing". In a
microlensing event, a star temporarily appears brighter than it really is
because another astronomical body is passing between it and observers on
Earth; the gravitational field of the intervening object affects the starlight in a
way similar to a lens.
If the intervening object is a star, it causes a characteristic signal that lasts
about a month. Any planets orbiting this star can produce significant
deviations in the signal, lasting days for giant planets down to hours for Earthmass planets. The probability of this happening is between 1.5% and 20%
depending on the mass of the planet.
The PLANET campaign performs nearly-continuous round-the-clock highprecision monitoring of ongoing microlensing events, sampling the lightcurve
at intervals that may be as little as few minutes with a world-wide network of
telescopes. The backbone of the network is formed by the Danish 1.54-m
telescope at the European Southern Observatory at La Silla (Chile), the
Canopus Observatory 1.0-m telescope (Tasmania, Australia), the Perth 0.6-m
telescope (Western Australia), and the Boyden 1.5-m telescope (South
Africa), which is supplemented by some other telescopes. PLANET will
share information and some resources with the microlensing campaign
performed with RoboNet, a UK robotic telescope network comprised of the
Liverpool 2.0-m (Canary Islands, Spain) and the two Faulkes 2.0-m telescopes
(Hawaii and Australia).
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
From the 500-700 microlensing events announced annually by the survey
campaigns OGLE and MOA that monitor tens of millions of stars on a daily
basis, PLANET focuses on up to 75 events that are selected as most suitable
candidates for the detection of planets around the intervening lens star. "If
20% of these stars are surrounded by planets, 10-15 giant planets and 1 or 2
terrestrial planets are expected to reveal their existence over three years of
operation", Dr. Dominik said.
While PLANET might detect a second Earth, its typical expected distance
would be 20,000 light years—much too far to think of establishing any
contact!
Contacts:
Dr. Martin Dominik
University of St. Andrews
School of Physics & Astronomy
North Haugh, St. Andrews
KY16 9SS United Kingdom
Phone: (+44)-(0)1334-463066
Fax: (+44)-(0)1334-463104
E-mail: md35@st-andrews.ac.uk
Dr. Jean-Philippe Beaulieu
Institut d'Astrophysique de Paris
98bis Boulevard d'Arago 75014 Paris France
Phone: +33-1-44-328119
Fax: +33-1-44-328001
E-mail: beaulieu@iap.fr
Read the original news release at
http://www.ras.org.uk/html/press/pn0414ras.html.
Additional articles on this subject are available at:
http://www.spacedaily.com/news/extrasolar-04j.html
http://spaceflightnow.com/news/n0403/31planets/
MOON-TO-MARS FEASIBLE, EXPERTS SAY, BUT POLITICS,
LACK OF INDUSTRY COOPERATION COULD JEOPARDIZE
VISION
By Leonard David
From Space.com
30 March 2004
President George W. Bush’s vision to send robotic and human explorers back
to the Moon, on to Mars and beyond can be made affordable and sustainable.
But turning rhetoric into reality will require drawing upon the talents of civil
and military abilities, as well as industrial prowess, policy and space
technologists participating in the 20th annual meeting of the National Space
Symposium said Tuesday.
Participating in the panel, "The New NASA Vision—How We Got Here.
What It Means," Bretton Alexander, Senior Policy Analyst at the White House
Office of Science and Technology Policy, outlined President Bush’s January
14th marching orders for NASA. Alexander said the tragic loss of the shuttle
Columbia early last year created a crisis in the civilian space sector,
compounded by the lack of a compelling vision for the nation’s human space
flight program. There has been a 30-year national debate as to the nation’s
space goals, he said, which President Bush has ended by setting the country
on a bold course for the 21st century.
James Kennedy, Director of NASA’s John F. Kennedy Space Center in
Florida urged that the Bush plan for space must be more than a partisan, onePresident commitment.
"I personally think it’s time, after Congress has spoken on this subject... it’ll
be time for this to be no longer the President’s vision. This should be depoliticized. It should be our national vision of space exploration," Kennedy
said. "I hope that we adopt that as our own personal vision."
Read the full article at
http://www.space.com/news/nss_moonmars_040330.html.
2
CAN INTELLIGENT LIFE THRIVE IN CLOSE QUARTERS? AN
INTERVIEW WITH CHRISTOPHER CHYBA
By Henry Bortman
From Astrobiology Magazine
31 March 2004
Christopher Chyba is the principal investigator for the SETI Institute lead
team of the NASA Astrobiology Institute. Chyba formerly headed the SETI
Institute's Center for the Study of Life in the Universe. His NAI team is
pursuing a wide range of research activities, looking at both life's beginnings
on Earth and the possibility of life on other worlds. One of his team's research
projects will explore a question critical to the search for extraterrestrial
intelligence. Can planets orbiting red dwarf M-type stars support life—
perhaps even intelligent life? Astrobiology Magazine's managing editor
Henry Bortman recently spoke with Chyba about Tarter's, Mancinelli's, and
Backus's research.
SETI's Jill Tarter (left), Peter Backus (center), and
Rocco Mancinelli (right). Image credit: SETI Institute.
Astrobiology Magazine: Jill Tarter and Peter Backus, and microbiologist
Rocco Mancinelli, all of whom are with the SETI Institute, are involved in the
search for extraterrestrial intelligence. Their contribution to your NAI team's
research will be to consider the habitability of M-class red dwarf stars, their
potential as SETI targets.
At a forum last winter, Frank Drake explained his famous Drake Equation,
which calculates the likelihood that there are other intelligent species in our
galaxy. One of the equation's factors, R*, has to do with the rate at which the
galaxy produces stars that provide environments capable of supporting
intelligent life. He said that a major
question in determining this factor had
to do with the habitability of M-class
stars. Of the 20 or so stars produced in
the galaxy each year, 15 of them are
dim M dwarfs. And so, if it turns out
that planets around M dwarfs could
support intelligent life, there would be
many more stars on the SETI target list
Of the 20 or so stars produced
than if M dwarfs were excluded. Is that
in the galaxy each year, 15 of
the question that Jill, Rocco and Peter
them are dim M dwarfs. Image
are hoping to answer?
credit: NASA.
Christopher Chyba: You're right on target. We're going to have a series of
workshops that involve project co-investigators and other people who are
experts in stellar evolution—and also biologists, microbiologists, and it's
likely we'll bring others in—to look at this question of the habitability of
worlds around M stars.
There are two reasons why that question is tough. One's mostly a red herring,
and the other is more significant. For a planet to be in the so-called habitable
zone of an M star, it has to be close enough to have liquid water. For a red
dwarf, that means it has to be real close, because the star is dim. But that also
means that it's going to be close enough that on a geologically short time span
it's going to be spin-locked, with the same side of the planet always facing the
star, the way the moon is with the Earth.
There was concern for a while—this is featured in Rare Earth—that that
would mean that all of the planet's atmosphere would freeze out on its dark
side, and that would be that. But, in fact, if you do the greenhouse
simulations—Joshi et al. published these results in 1997— for those kinds of
worlds, you find that you need only around a tenth of a bar of carbon dioxide
to give you a thick enough atmosphere, enough greenhouse effect, that you
redistribute the heat so that your atmosphere doesn't freeze out. That's a lot
more carbon dioxide than we have on Earth, but well within the range of
what's plausible.
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
If you get up into the range of a bar or so of carbon dioxide, not only does
your atmosphere not freeze out, but you stay warm on both sides of the planet,
so you have liquid water potentially all over the planet. You have no
guarantees that a planet around an M dwarf will have that much carbon
dioxide. But you don't have any guarantee of having the atmosphere you want
on a planet around a G-class (sun-like) star, either. So I don't think that's a
decisive problem, although we will certainly revisit that.
The other issue, though, has to do with flaring from those stars. Its radiation
environment might be too harsh for life on planets around M stars, although
papers published as early as 1991 called this into question. And that's
something that we need a much better understanding of, astrophysically and
atmospherically. We also want to have biologists in the picture so that we can
get a better handle on just how challenging the radiation and ultraviolet
environments would be either for microscopic life or for more sophisticated
forms of life. And that will ultimately lead to an operational decision about
whether or not we expand the list of target stars for our SETI search to include
M stars. Remember, as Frank said, these are 75 percent of the nearby stars.
So answering this question will have a huge impact on our search strategy.
3
still entirely possible that there's no life anywhere else in the known universe
other than Earth—we don't have definite evidence that there's life anywhere
else—there has been a whole series of discoveries that make it seem more
plausible that there's extraterrestrial life. So I think that's the intellectual
context. And there's a lot of enthusiasm in Congress now.
The other thing to mention is that there is a standing committee of the
National Academy of Sciences National Research Council, the Committee on
the Origin and Evolution of Life, which was asked by Congress to do a report
on astrobiology, and in particular to assess the role of SETI in astrobiology.
And that committee's report is effusive in its praise for SETI and, to be frank,
the SETI Institute, so I think that played a role, too, because that represented
outside support. So I think a lot of things came together in the space of the
last few years.
Read the original article at http://www.astrobio.net/news/article901.html.
LIFE BENEATH THE ICE IN THE OUTER SOLAR SYSTEM?
Royal Astronomical Society press notice PN04-10
31 March 2004
At present, we know of no worlds beyond our Earth where life exists.
However, primitive organisms on our planet have evolved and adapted over
billions of years, colonizing the most inhospitable places. Since life seems to
gain a foothold in the most hostile environments, it seems distinctly possible
that living organisms could exist in ice-covered oceans on worlds far from the
Sun, according to Dr. David Rothery (Open University), who will be speaking
today at the RAS National Astronomy Meeting in Milton Keynes.
Left: Frank Drake, whose famous Drake Equation calculates
the likelihood that there are other intelligent species in our
galaxy. Right: Christopher Chyba, principal investigator for
NASA Astrobiology Institute's SETI lead team. Image credit:
SETI Institute.
AM: I'm surprised that NASA is funding a research project whose focus is the
search for extraterrestrial intelligence. I was under the impression that NASA
was forbidden by Congress from funding SETI.
CC: No, that's no longer the case. Let me clarify, and then explain what's
changed, because this is something that has often caused confusion. There
was never any prohibition against NASA funding research projects out of the
SETI Institute. What the prohibition was understood to be—really,
misunderstood to be—was a prohibition against funding SETI science,
whether it was the SETI Institute, or the Harvard SETI project, or the
Berkeley SETI project, or any other SETI project. The interpretation was that
they were not permitted to fund that entire area of science.
What was really the case was that Congress zeroed SETI research out of the
NASA budget in '93—but that was a one-time elimination from the budget.
There wasn't any language saying, "You shall never fund SETI research ever
again." But it was interpreted that way, and I understand that. A government
agency thinks it gets a directive from Congress and it wants to be faithful to
that.
What's changed is that the sense of Congress is different now. And you can
see that back to at least 2001, when the Aeronautics and Space Subcommittee
of the House Science Committee held a hearing on life in the universe, and
they had four or five people testifying, including myself. I testified mostly
about astrobiology and how SETI is a natural component of the continuum of
questions asked in astrobiology. And there was a clear sense of the committee
at that time, at the hearing, that SETI was part of astrobiology. In fact, this led
to a statement that NASA would consider SETI science projects equally under
peer review with other projects that fit within astrobiology. That is to say,
NASA could make these decisions on the basis of peer review, rather than on
the basis of some extra-scientific reason. That was, after all, reflected in the
new Astrobiology Roadmap, which for the first time includes SETI as a
component of astrobiology. And the funding for a SETI project within this
proposal is just a kind of natural outcome of that process.
This image of Jupiter's icy satellite Europa shows surface features such as
domes and ridges, as well as a region of disrupted terrain including crustal
plates which are thought to have broken apart and "rafted" into new
positions. The image covers an area of Europa's surface about 250 by 200
kilometer (km) and is centered at 10 degrees latitude, 271 degrees longitude.
The color information allows the surface to be divided into three distinct
spectral units. The bright white areas are ejecta rays from the relatively
young crater Pwyll, which is located about 1000 km to the south (bottom) of
this image. These patchy deposits appear to be superposed on other areas of
the surface, and thus are thought to be the youngest features present. Also
visible are reddish areas which correspond to locations where non-ice
components are present. This coloring can be seen along the ridges, in the
region of disrupted terrain in the center of the image, and near the dome-like
features where the surface may have been thermally altered. Thus, areas
associated with internal geologic activity appear reddish. The third distinct
color unit is bright blue, and corresponds to the relatively old icy plains.
Image credit: NASA/University of Arizona.
But you're right, in the sense that that's a shift in at least perception in the last
few years. And I think a few things have happened. One is that, while it's
Europa is the innermost of Jupiter's large icy satellites. It is slightly smaller
than our own Moon, but its rocky interior is hidden beneath a 100 km blanket
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
of ice. There has been much speculation as to whether the ice remains solid
right down to the moon's rocky interior, or whether it consists of a thinner ice
sheet floating on an ocean of water. Data from NASA's Galileo spacecraft,
which orbited Jupiter from 1995 until 2003, provided detailed insights into
Europa's structure that will not be surpassed until the arrival of NASA's
Jupiter Icy Moons Orbiter (which may not be until 2023).
The high-resolution Galileo images and other data revolutionized our
knowledge of Europa's surface and interior structure, making it seem more
likely that the ice is (at least at some times and in some places) relatively thin
(much less than 10 km) and overlying a liquid water ocean. The images
showed localized areas of "melt-through" demonstrated by "chaos" regions,
where detached rafts of the icy shell can be seen dispersed in a now-refrozen
matrix. The cause of melt-through is likely to be tidal heating, which is
especially strong within Europa because it orbits within the immense gravity
of Jupiter and experiences competing tidal pulls from the large, neighboring
moons, Io and Ganymede. This process also powers the widespread volcanic
eruptions on Io.
4
have arisen in just the same way. If so, life could survive there today,
supported by chemical energy in the same way that the hydrothermal vents on
Earth's ocean floors support ecosystems that do not depend on sunlight.
"Episodes of tidal heating in some of the Solar System's other icy bodies could
equally well have given rise to life, even in such remote bodies as the newly
discovered, remote planetoid Sedna if, as has been suggested, it has a satellite
with which to interact tidally," said Dr. Rothery. "However, only in the case
of Europa, and perhaps a few other satellites of the giant planets, does it seem
plausible that life could flourish in the long term."
Contact:
Dr. David A. Rothery
Department of Earth Sciences
The Open University
Milton Keynes MK7 6AA
Phone: +44 (0)1908 652124
Fax: +44 (0)1908 655151
Mobile: +44 (0)7986-260258
E-mail: d.a.rothery@open.ac.uk
Further information and images can be found on the web at the NASA Galileo
Web site:
http://galileo.jpl.nasa.gov/
http://galileo.jpl.nasa.gov/images/europa/eurimages.html
http://galileo.jpl.nasa.gov/images/europa/eurchaotic.html
Read the original news release at
http://www.ras.org.uk/html/press/pn0410ras.html.
Additional articles on this subject are available at:
http://www.spacedaily.com/news/outerplanets-04c.html
http://spaceflightnow.com/news/n0403/30europalife/
http://www.universetoday.com/am/publish/is_life_europa.html
TITAN'S LAPPING OIL WAVES
Based on a Royal Astronomical Society report
From Astrobiology Magazine
31 March 2004
When the European Huygens probe on the Cassini space mission parachutes
down through the opaque smoggy atmosphere of Saturn's moon Titan early
next year, it may find itself splashing into a sea of liquid hydrocarbons. In
what is probably the first piece of "extraterrestrial oceanography" ever carried
out, Dr. Nadeem Ghafoor of Surrey Satellite Technology and Professor John
Zarnecki of the Open University, with Drs. Meric Srokecz and Peter
Challenor of the Southampton Oceanography Centre, calculated how any seas
on Titan would compare with Earth's oceans. Their results predict that waves
driven by the wind would be up to 7 times higher but would move more
slowly and be much farther apart. The team worked with a computer
simulation, or "model", that predicts how wind-driven waves on the surface of
the sea are generated on Earth, but they changed all the basic inputs, such as
the local gravity, and the properties of the liquid, to values they might expect
on Titan.
These artist's drawings depict two proposed models of the subsurface
structure of the Jovian moon, Europa. Geologic features on the surface,
imaged by the Solid State Imaging (SSI) system on NASA's Galileo spacecraft
might be explained either by the existence of a warm, convecting ice layer,
located several kilometers below a cold, brittle surface ice crust (top model),
or by a layer of liquid water with a possible depth of more than 100
kilometers(bottom model). If a 100 kilometer (60 mile) deep ocean existed
below a 15 kilometer (10 mile) thick Europan ice crust, it would be 10 times
deeper than any ocean on Earth and would contain twice as much water as
Earth's oceans and rivers combined. Unlike the Earth, magnesium sulfate
might be a major salt component of Europa's water or ice, while the Earth's
oceans are salty due to sodium chloride (common salt). Image credit:
NASA/SETI Institute.
There may be occasional volcanic eruptions onto Europa's ocean floor—rather
like a less active, ice-covered version of Io—or, more likely, hot springs
where chemically-enriched water heated by passage through the rock reemerges on the ocean floor. This sort of environment is currently regarded as
the most likely place for life on Earth to have begun, and life on Europa could
Arguments about the nature of Titan's surface have raged for a number of
years. Following the flyby of the Voyager 1 spacecraft in 1980, some
researchers suggested that Titan's concealed surface might be at least partly
covered by a sea of liquid methane and ethane. But there are several other
hypotheses, ranging from a hard icy surface at one extreme to a near-global
hydrocarbon ocean at the other. Other variants include the notion of
hydrocarbon "sludge" overlying an icy surface. Planetary scientists hope that
the Cassini/Huygens mission will provide an answer to this question, with
observations from Cassini during several flybys of Titan and from Huygens,
which will land (or splash) on 14 January 2005.
The idea that Titan has significant bodies of surface liquid has recently been
reinforced by the announcement that radar reflections from Titan have been
detected using the giant Arecibo radio dish in Puerto Rico. Importantly, the
returned signals in 12 out the 16 attempts made contained reflections of the
kind expected from a polished surface, like a mirror. (This is similar to seeing
a blinding patch of light on the surface of the sea where the Sun is being
reflected.) The radar researchers concluded that 75% of Titan's surface may be
covered by "open bodies of liquid hydrocarbons"—in other words, seas.
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
The exact nature of the reflected radar signal can be used to determine how
smooth or choppy the liquid surface is. This interpretation says that the slope
of the waves is typically less than 4 degrees, which is consistent with the
predictions of the British scientists, who showed that the maximum possible
slope of waves generated by wind speeds up to 7 mph would be 11 degrees.
"Hopefully ESA's Huygens probe will end the speculation" says Dr Ghafoor.
"Not only will this be by far the most remote soft landing of a spacecraft ever
attempted but Huygens might become the first extraterrestrial boat if it does
indeed land on a hydrocarbon lake or sea."
5
Aurora program, with the ultimate aim of landing people on Mars by 2033,
while the US has recently redirected its human space activities towards a
return to the Moon.
On Friday 2 April, Dr. Ian Crawford, a planetary scientist based at Birkbeck
College, London, will be explaining to the RAS National Astronomy Meeting,
held at the Open University in Milton Keynes, that there are indeed strong
scientific reasons for sending people back to the Moon and on to Mars. These
arguments are further developed in an article published in the April issue of
the Royal Astronomical Society's journal Astronomy & Geophysics, which is
timed to coincide with the meeting.
"The reasons for exploring the Moon and Mars are both very strong, but rather
different," said Dr. Crawford. "The importance of the Moon results from its
extremely ancient surface, which preserves a record of early Solar System
history that is not preserved anywhere else. On the other hand, the main
reason for wanting to explore Mars is to search for past or present life on the
planet, which is probably one of the most important scientific questions of our
time."
Given that strong scientific cases exist for a human return to the Moon and for
sending people on to Mars, Dr. Crawford argues that the two should be
combined in a self-consistent, international strategy for Solar System
exploration. Europe's Aurora program could be a major part of such a
strategy. The UK will shortly have to decide whether or not to participate in
the human spaceflight aspects of Aurora, and Dr. Crawford believes that we
should seize this unique opportunity to play a leading role in these exciting
endeavors.
Huygens parachutes onto Titan. ESA's Huygens probe descends through
Titan's mysterious atmosphere to unveil the hidden surface (artist's
impression). Image credit: ESA.
Although not designed specifically to survive landing or to float, the chances
it will do so are reasonable. However, the link back to Earth from Huygens
via Cassini, which will be flying past Titan and acting as a relay, will only last
for a maximum of 2 hours. During this time, if the probe is floating on a sea,
one of the 6 instruments Huygens is carrying, the Surface Science Package
experiment, which is led by John Zarnecki, will be making oceanography
measurements. Among the 9 sensors that it carries are ones that will measure
the height and frequency of the waves and also the depth of the sea using
sonar. It will also attempt to determine the composition of the sea.
What would the sea look like?
"Huygens does carry a camera so it is possible we shall have some direct
images," says Professor Zarnecki, "but let's try to imagine that we are sitting
onboard the probe after it has landed in a Titan ocean. What would we see?
Well, the waves would be more widely dispersed than on Earth but they will
be very much higher—mostly as a result of the fact that Titan gravity is only
about 15% of that on Earth. So the surface around us would probably appear
flat and deceptively calm, but in the distance we might see a rather tall, slowmoving wave advancing towards us—a wave that could overwhelm or sink
us."
Read the original article at http://www.astrobio.net/news/article902.html.
Additional articles on this subject are available at:
http://www.astrobio.net/news/article904.html
http://www.spacedaily.com/news/saturn-titan-04e.html
http://www.universetoday.com/am/publish/new_images_titan_vlt.html
HUMAN EXPLORATION OF THE MOON AND MARS
Royal Astronomical Society press notice PN04-09
31 March 2004
These are exciting times for space exploration. For the first time in a
generation, human missions beyond Earth orbit are being seriously considered
by space agencies on both sides of the Atlantic. Europe has initiated the
Given the difficulties of sending people to Mars, Dr. Crawford argues that it
would be wiser, initially, to concentrate human spaceflight activities on the
Moon. This would not only teach us much about the Moon and its history, but
also help pave the way for later human missions to Mars by developing the
necessary technology and expertise. However, the robotic exploration of
Mars could, and should, continue in parallel with a manned lunar program.
"By pursuing parallel programs to build up a human spaceflight capability on
the Moon and to advance robotic Mars exploration, there is a realistic chance
that we will have developed both the human spaceflight expertise and the
detailed knowledge of the martian environment to make human missions to
the Red Planet both scientifically worthwhile and technically feasible before
the middle of this century," said Dr. Crawford.
Contact:
Dr. Ian Crawford
School of Earth Sciences
Birkbeck College
Malet Street,
London, WC1E 7HX
Phone: +44 (0)207-679-3431
Mobile: +44 (0)777-62-34317
E-mail: i.crawford@ucl.ac.uk
Read the original news release at
http://www.ras.org.uk/html/press/pn0409ras.html.
An additional article on this subject is available at
http://www.spacedaily.com/news/mars-base-04f.html.
METHANE DETECTION POINTS TO LIFE ON MARS
By Robert Zubrin
Mars Society release
31 March 2004
Over the past week a series of discoveries have been announced that radically
enhance the prospects for the search for life on Mars.
The first
announcements came for the MER science team led by Cornell University
geologist Steven Squyres which identified the Meridani Planum landing site
of the Opportunity rover as the shoreline of an ancient salty sea. "If you want
to look for fossils, this is the place to go," NASA Associate Administrator for
Space Science Ed Weiler commented.
As exciting as the MER results were, however, they were superceded two
days later by the results of the team of V. A. Krasnopolsky, J. P. Mailard, and
T. C. Owen, who published a paper announcing that, using the Canada-
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
France-Hawaii telescope, they had detected methane in the martian
atmosphere at a level of about 11 ppb. As small as this concentration is, it is
anomalous, and cannot be explained by abiotic processes. We quote directly
from the Krasnopolsky team's abstract, entitled "Detection of Methane in the
Martian Atmosphere: Evidence for Life."
"...We detected the absorption by martian methane at a 3.9 sigma level. The
observed CH4 mixing ratio is 11 ±4 ppb. Total photochemical loss of CH4 in
the martian atmosphere is equal to 180,000/cm2-s, and the CH4 lifetime is 440
years. Heterogeneous loss of atmospheric methane is probably negligible,
while the sink of CH4 during its diffusion through the regolith may be
significant. There are no processes of CH4 formation in the atmosphere, so
the photochemical loss must therefore be balanced by abiogenic and biogenic
sources. The mantle outgassing of CH4 is 4000/cm2-s on the Earth, and
smaller by an order of magnitude on Mars [i.e., much smaller than the
required 180,000/cm2-s to make up the loss rate -RZ]. The calculated
production of CH4 by cometary impacts is 2.3 percent of the methane loss.
Methane cannot originate from an extinct biosphere, as in the case of "natural
gas" on Earth, given the exceeding low limits on organic matter set by the
Viking landers and the dry recent history which has been extremely hostile to
the macroscopic life needed to generate the gas. Therefore, methanogenesis
by living subterranean organisms is the most likely explanation for this
discovery. Our estimates of the biomass and its production using the
measured CH4 abundance show that the martian biota may be extremely
scarce and that Mars may be generally sterile except for some oases."
One day after the publication of the Krasnopolsky group abstract, two more
teams let it be known that they had measured similar results. One of the
teams, led by Mike Mumma of NASA Goddard Spaceflight Center, used
NASA's Infrared Telescope Facility in Hawaii and the international Gemini
South observatory in Chile to make its measurements. The other team, led by
Professor Vittorio Formisano, head of research of the Italian National Council
for Research's Institute of Physics and Interplanetary Space, used the
Planetary Fourier Spectrometer instrument on the ESA Mars Express
spacecraft. Both the Formisano group and the Mumma group reported
methane measurements in the 10 to 10.5 ppb range, in excellent agreement
with each other and the 11 ppb results reported by the Krasnopolsky team.
So we now have three teams, using four different instruments, all reporting
nearly identical methane measurements. The evidence for validity of the
measurements must therefore be taken as very strong, and the key questions
are those relating to interpretation, significance, and necessary follow-up.
6
While alternative (a) is possible in principle, it is the least likely of the three,
since natural material transfer from Mars to Earth (via meteoritic impact) is
easier than from Earth to Mars, and since Mars cooled quicker than the Earth
(both planets were originally molten), life would have had an opportunity to
originate on Mars first. Furthermore, one to the great mysteries about life on
Earth is that we find no free-living organisms on Earth simpler than bacteria,
which are actually highly complex—much too complex to represent the first
life forms to emerge from chemistry. This anomaly has led numerous
investigators since the 19th Century to suggest that life may not have
originated on Earth at all, but represent an immigrant phenomenon. This
leaves us with (b) or (c).
If (b) is true, and Mars is the homeland of life, then by going to Mars we have
the possibility of discovering free-living life forms more primitive than
bacteria, and who therefore present a living record of the missing links
between chemistry and life. By examining them, we could read the book of
life itself, and finally gain an understanding of the process that allowed for the
creation of all living things.
If (c) is true, we would find no free-living organisms on Mars simpler than
archaic bacteria of similar plan to those observed on Earth. In that case, we
would have proof that the planets of our solar system were seeded early in
their history by bacterial spores transported across interstellar space. This
would be proof of the [hypothesis] of panspermia, and its inevitable
consequence that life is present on billions of planets across our galaxy.
Alternatively, if (1) is false, then (2) must be true, in which case what we have
on Mars is a second genesis. If this is the case, it would also imply that life is
a general phenomenon in the universe, since we would have proof through
success stories in two out of two cases that life tends to develop from non-life
wherever it has an acceptable physical environment. Furthermore, however,
the existence of such a second genesis would provide us with an opportunity
to determine whether the biochemical plan of life that is common to all Earth
life-forms is the pattern for all life everywhere, or whether we are just one
peculiar example of a much vaster and more diverse tapestry of life that
pervades the cosmos.
In other words, the detection of life on Mars is an invitation to an
investigation whose results could provide us answers to the most profound
questions humans have ever asked concerning the origin and fundamental
nature of life.
Follow-up
Interpretation
For reasons explained in the Krasnopolsky abstract quoted above, the most
likely interpretation is that the methane is a product of the metabolism of
indigenous microbes. Methanogenic bacteria are common on Earth, and
include members of the most archaic subgroup of bacterial life. The MER
results show conclusively that surface environments that could have hosted
rich microbial ecologies once existed on Mars, and geologically recent runoff
channels imaged by Mars Global Surveyor (MGS) strongly indicate that
subsurface reservoirs that could host microbes probably exist on Mars today.
The alternative explanation, that the methane is a product of geothermal
activity, appears unlikely in view of the TES and THEMIS measurements
taken by NASA's MGS and Mars Odyssey orbiters. Either of these spacecraft
should have been able to detect the thermal emissions associated with such
activity, but they have not. This makes the geothermal explanation for the
origin of the martian methane almost untenable. Furthermore, if somehow
such hydrothermal environments did exist regardless, then they themselves
would provide wonderful candidate environments for a host of microbial life
forms. So, while not constituting definitive proof, the preponderance of the
evidence strongly points to life.
Significance
The significance of the detection of life on Mars is enormous. There are two
possibilities:
1. The life detected on Mars has a common origin with Earth life.
2. The life detected on Mars has a separate origin from Earth life.
Within the common origin possibility (1), there are three alternatives:
a.
Mars life is descended from Earth life.
b. Earth life is descended from Mars life.
c.
Both Earth life and Mars life are descended from a third source.
The key issue therefore, is not whether there is life on Mars, but what is the
life on Mars. To answer that question, drilling rigs will need to be set up on
the martian surface capable of penetrating down to the locations of the
subsurface liquid reservoirs which host the martian microbes, and water
samples extracted. The water samples will then need to be cultured to see if
they contain microbes, and if they do, then the microbes need to be imaged
through a variety of techniques and subjected to a battery of biochemical tests.
This sort of investigation can be carried out only by human explorers
operating on the surface of Mars. NASA's new Space Exploration Initiative
has just been handed its mission assignment.
An in-depth discussion of the significance of the methane detection discovery
for the search for life on Mars will be held at the 7th International Mars
Society Convention, Palmer House Hilton, Chicago, IL, August 19-22, 2004.
Registration is now open at www.marssociety.org.
For further information about the Mars Society, visit our web site at
www.marssociety.org.
MOLECULAR MIDWIVES HOLD CLUES TO THE ORIGIN OF LIFE
From SpaceDaily
1 April 2004
Adding a small molecule, dubbed a "molecular midwife," researchers
increased the rate of DNA formation in a chemical reaction 1,000 fold over a
similar reaction lacking a midwife. The discovery is an important step in the
effort to trace the evolution of life back to the earliest self-replicating
molecules. The results are reported in the April 2 edition of the German
chemistry journal Angewandte Chemie.
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
"We are working to uncover how molecules similar to RNA and DNA first
appeared on Earth around 4 billion years ago. Our theory is that small, simple
molecules acted as templates for the production of the first RNA-like
molecules. Many of these small molecules, or molecular midwives, would
have worked together to produce RNA by spontaneously mixing and
assembling with the chemical building blocks of RNA," said Nicholas Hud,
associate professor of chemistry and biochemistry at the Georgia Institute of
Technology.
Read the full article at http://www.spacedaily.com/news/life-04zl.html.
PLANETARY SYSTEMS WITH HABITABLE EARTHS?
Royal Astronomical Society press notice PN04-13
1 April 2004
More than 100 planetary systems have already been discovered around distant
stars. Unfortunately, the limitations of current technology mean that only
giant planets (like Jupiter) have so far been detected, and smaller, rocky
planets similar to Earth remain out of sight. How many of the known
exoplanetary systems might contain habitable Earth-type planets? Perhaps
half of them, according to a team from the Open University, led by Professor
Barrie Jones, who will be describing their results today at the RAS National
Astronomy Meeting in Milton Keynes.
7
been in this zone for at least one billion years. This period of time has been
selected since it is thought to be the minimum required for life to arise and
establish itself. Furthermore, the models show that life could develop at some
time in about two thirds of the systems, since the habitable zone moves
outwards as the central star ages and becomes more active.
Habitable moons
A different aspect of this problem is being studied by PhD student David
Underwood, who is investigating the possibility that Earth-sized moons
orbiting giant planets could support life. A poster setting out the possibilities
will be presented during the RAS National Astronomy Meeting.
All of the planets discovered so far are of similar mass to Jupiter, the largest
planet in our Solar System. Just as Jupiter has four planet-sized moons, so
giant planets around other stars may also have extensive satellite systems,
possibly with moons similar in size and mass to Earth. Life as we know it
cannot evolve on a gaseous, giant planet. However, it could survive on Earthsized satellites orbiting such a planet if the giant is located in the habitable
zone.
In order to determine which of the gas giants located within habitable zones
could possess a life-friendly moon, the computer models search for systems
where the orbits of Earth-sized satellites would be stable and confined within
the habitable zone for at least the one billion years needed for life to emerge.
The OU team's method of determining whether any putative "Earths" or
Earth-sized satellites in habitable zones can offer suitable conditions for life to
evolve can be applied rapidly to any planetary systems that are newly
announced. Future searches for "Earths" and extraterrestrial life should also
be assisted by identifying in advance the systems most likely to house
habitable worlds.
The predictions made by the simulations will have a practical value in years to
come when next-generation instruments will be able to search for the
atmospheric signatures of life, such as large amounts of oxygen, on "Earths"
and Earth-sized satellites.
Background
There are currently 105 known planetary systems other than our own, with
120 Jupiter-like planets orbiting them. Two of these systems contain three
known planets, 11 contain two and the remaining 92 each have one. All but
one of these planets has been discovered by their effect on their parent stars'
motion in the sky, causing them to wobble regularly. The extent of these
wobbles can be determined from information within the light received from
the stars. The remaining planet was discovered as the result of a slight
dimming of starlight caused by its regular passage across the disk of its parent
star.
Extrasolar planets have been found around stars in all regions of the sky as
viewed from Earth. How many have earthlike planets? Image credit: S. G.
Korzennik.
By using computer modeling of the known exoplanetary systems, the group
has been able to calculate the likelihood of any 'Earths' existing in the socalled habitable zone—the range of distances from each central star where life
as we know it could survive. Popularly known as the "Goldilocks" zone, this
region would be neither too hot for liquid water, nor too cold.
By launching "Earths" (with masses between 0.1 and 10 times that of our
Earth) into a variety of orbits in the habitable zone and following their
progress with the computer model, the small planets have been found to suffer
a variety of fates. In some systems the proximity of one or more Jupiter-like
planets results in gravitational ejection of the "Earth" from anywhere in the
habitable zone. However, in other cases there are safe havens in parts of the
habitable zone, and in the remainder the entire zone is a safe haven.
Nine of the known exoplanetary systems have been investigated in detail
using this technique, enabling the team to derive the basic rules that determine
the habitability of the remaining ninety or so systems. The analysis shows
that about half of the known exoplanetary systems could have an "Earth"
which is currently orbiting in at least part of the habitable zone, and which has
Future discoveries are likely to contain a higher proportion of systems that
resemble our Solar System, where the giant planets orbit at a safe distance
beyond the habitable zone. The proportion of systems that could have
habitable "Earths" is, therefore, likely to rise. By the middle of the next
decade, space telescopes should be capable of seeing any "Earths" and
investigating them to see if they are habitable, and, indeed, whether they
actually support life.
Contacts:
Professor Barrie W. Jones
Physics & Astronomy Department
Open University
Milton Keynes MK7 6AA
Phone: +44 (0)1908-653229
E-mail: b.w.jones@open.ac.uk
David R. Underwood,
Open University (see above)
Phone: +44 (0)1908-652123,
E-mail: b.w.jones@open.ac.uk
Further information and images can be found on the web at The Extrasolar
Planets Encyclopedia (http://www.obspm.fr/encycl/encycl.html).
Read the original news release at
http://www.ras.org.uk/html/press/pn0413ras.html.
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
Additional articles on this subject are available at:
http://www.astrobio.net/news/article903.html
http://www.spacedaily.com/2004/040401171808.gnpjy4di.html
http://www.spacedaily.com/news/extrasolar-04i.html
http://spaceflightnow.com/news/n0403/31habitable/
http://www.universetoday.com/am/publish/how_many_habitable_earths.html
8
Additional articles on this subject are available at:
http://www.spacedaily.com/news/mars-exomars-04d.html
http://spaceflightnow.com/news/n0404/03marssample/
http://www.universetoday.com/am/publish/mars_sample_return_two_directio
ns.html
SPACE DEFINES MARS SAMPLE RETURN MISSION
EADS Astrium press release
CHEAP COMMUNICATION SCHEMES FOR ET
By Seth Shostak
From Space.com
1 April 2004
1 April 2004
Following award of the study contract by ESA, EADS Space has made
significant progress in completing the first definition of a European Mars
Sample Return (MSR) mission. While EADS Astrium is defining the overall
mission and the spacecraft, EADS Space Transportation is responsible for the
re-entry systems and a "Mars Ascent Vehicle"—a small rocket to carry the
precious sample up through the martian atmosphere. The team at EADS
Astrium, Stevenage is currently preparing for the Mid Term Review where
two very different designs will have to be reduced to one.
When it comes to signaling across space, power is paramount. Project
Phoenix, which just wrapped up nine years of observations, was an acutely
sensitive search for radio broadcasts. The experiment could have discerned an
alien signal that was wafting a mere 0.00000000000000000001 watts onto the
Arecibo telescope’s Cyclopean, twenty-acre aluminum mirror. I’ll state the
obvious: that’s a small number. Indeed, if that incoming energy were
collected for the length of time from the Big Bang until today (that is to say,
for all time), the total would only be enough to blink a flashlight for a
thousandth of a second.
In the first concept the launch vehicle lifts the sample from the surface of
Mars and docks with the Earth Return Vehicle. In the second concept the
launch vehicle releases the sample container into a low Mars orbit and the
Earth Return Vehicle uses a capture mechanism to perform the rendezvous.
The selection of the rendezvous concept has a significant impact on the
overall mass, cost and complexity of the mission.
Marie-Claire Perkinson, Senior Systems Engineer at EADS Astrium,
Stevenage, leading the study said. "Our industrial team, which includes
EADS Space in France; Galileo Avionica in Italy, Sener in Spain and Utopia
Consultancies in Germany has done a great job so far in proposing the two
exciting concepts. We now have to select the best solution and then, once
ESA has raised the appropriate support and funds for the implementation of
the mission, launch could be as early as 2011."
Background
European astronauts may land on Mars one day, but getting them there and
safely returning them to Earth will involve many steps and numerous
technical challenges in propulsion, structures, computers and software. It will
require sophisticated spacecraft to escape from Earth's orbit; fly to Mars,
survive atmospheric entry and landing; operate on the surface; take-off; return
to Earth and then finally get the crew back on terra firma. Long before this
can be accomplished some key technologies must be demonstrated. The best
way to do this is to fly a robotic mission with a scaled-down version of the
eventual manned mission. This is exactly the goal of Mars Sample Return,
the second flagship mission of the European Space Agency's Aurora planetary
exploration initiative and one of the most eagerly awaited future space
missions for the planetary scientists.
Because martian winds have transported dust across the planet's surface over
millions of years, the MSR sample could include particles from many
different sources, representing a wide variety of rock types and ages, like
grains of sand on a beach. Each granule could offer completely different
insights into the rich geologic past of the Red Planet. Scientists could now
"look at the sample as if each grain were a rock," said Professor Colin
Pillinger of the Open University. This would build on the decades of research
already carried out on lunar rock samples.
EADS Space has used its unique heritage in building launch vehicles,
planetary spacecraft and re-entry systems, combined with a deep
understanding of the science goals to win the ESA mission study. ESA's
Aurora Project Manager Bruno Gardini said "The Mars Sample Return
mission is one of the most challenging missions ever considered by ESA. Not
only does it include many new technologies and four or five different
spacecraft, but it is also a mission of tremendous scientific importance and the
first robotic mission with a similar profile to a possible human expedition to
Mars."
Contact:
Alistair Scott
EADS Space (UK)
Phone: +44 (0)1438-77-3698
Mobile: +44 (0)7887-826264
Still, if you work out what sort of effort is required to produce that pipsqueak
signal, the numbers get large. At 100 light-years distance, and assuming that
the aliens are broadcasting in all directions equally, our cosmic buddies would
need to pump their transmitter with 100 billion watts in order to drop that
miniscule amount of power onto the Arecibo dish. That’s more than produced
by all of America’s electric utility plants.
Of course, the extraterrestrials could be clever about their attempts to signal.
For example, a rotating antenna might target only the flat part of the Milky
Way Galaxy, sweeping it like a lighthouse beacon and doing so with
considerably less juice than would be required by the all-sky, all-the-time
approach. Another scheme would be for the aliens to use antenna arrays that
sequentially "pinged" only interesting star systems. Again, this would save on
the electric bills. Still, there’s no doubt that any of these transmitting schemes
would be big-time undertakings, involving large structures, hefty electronics,
and gobs of power.
Read the full article at
http://www.space.com/searchforlife/seti_targeted_040401.html.
ASHES OF THE PHOENIX
By Peter Backus
From Astrobiology Magazine
4 April 2004
Project Phoenix has left the building. There are empty spaces at Arecibo
Observatory, but not for long. A new computer cluster is destined for the
space occupied by fifteen Programmable Detection Modules. The cabinets
that stored the spare components for the Phoenix search system are already
reassigned to the RFI Monitoring and Electronics groups.
For the staff at Arecibo, another SETI project has ended, and life at the
observatory goes on. But for us, life is in transition as we wrap up one project
and begin another. As we wait in California for our equipment to arrive from
Puerto Rico, it is a good time to look back on Project Phoenix. It wasn't "just
another" SETI project.
Phoenix rose from the ashes of the NASA SETI Program that was terminated
by the US Congress in 1993. The SETI Institute secured use of some of the
search equipment developed for NASA under a long-term loan agreement and
raised private funds to conduct a search. In the following year, Institute
scientists and engineers doubled the size of the search system. In February
1995, just one month after the original NASA schedule, Project Phoenix
began its targeted search of nearby stars.
The origin of Phoenix, while unusual, is not the reason it was unlike any other
SETI project. Phoenix observed hundreds of stars over billions of frequency
channels, with high sensitivity, and real-time signal detection and verification.
No other search can compare on any aspect. A few searches have looked at
some nearby stars in specific frequency bands. Phoenix observed more than
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
700 stars, using some of the world's largest telescopes, over all available
frequencies between 1200 and 3000 MHz with channels only 0.7 Hz wide.
9
An additional article on this subject is available at
http://www.spacedaily.com/news/seti-04b.html.
EUROPA: LIVING WORLD OR FROZEN WASTELAND? AN
INTERVIEW WITH CHRISTOPHER CHYBA
By Henry Bortman
From Astrobiology Magazine
5 April 2004
Christopher Chyba is the principal investigator for the SETI Institute lead
team of the NASA Astrobiology Institute (NAI). Chyba formerly headed the
SETI Institute's Center for the Study of Life in the Universe. His NAI team is
pursuing a wide range of research activities, looking at both life's beginnings
on Earth and the possibility of life on other worlds. Several of his team's
research projects will examine the potential for life—and how one might go
about detecting it—on Jupiter's moon Europa. Astrobiology Magazine's
managing editor Henry Bortman recently spoke with Chyba about this work.
Astrobiology Magazine: One of the areas of focus of your personal research
has been the possibility of life on Jupiter's moon Europa. Several of the
projects funded by your NAI grant deal with this ice-covered world.
Christopher Chyba: Right. We're interested in interactions of life and
planetary evolution. There are three worlds that are most interesting from that
point of view: Earth, Mars and Europa. And we have a handful of projects
going that are relevant to Europa. Cynthia Phillips is the leader of one of
those projects; my grad student here at Stanford, Kevin Hand, heads up
another one; and Max Bernstein, who's a SETI Institute P.I., is a leader on the
third.
In a universe brimming with stars, the search is on to find out whether life
exists elsewhere. Image credit:NASA/STScI/ESA.
A few searches have used large telescopes, but they typically scan the sky and
are limited to a single frequency band. Most of the time, these searches do not
observe stars in our galaxy, but are actually looking at stars millions of light
years away. In the fraction of time they observe stars in the Milky Way, they
only spend 10 to 20 seconds per star. Phoenix only observed nearby stars in
our galaxy and so could devote from 100 to 550 seconds per star per
frequency band.
Almost all previous searches have one thing in common, unresolved signals.
When you search for communication signals from interstellar distances, you
will certainly detect signals from the Earth and its satellites. Phoenix
perfected the real-time processing and verification techniques pioneered by
Paul Horowitz of Harvard University. In a two-stage pipeline, Phoenix
collected data and detected signals. Any signals not in a database of recent
terrestrial interference were subjected to a type of observation unique to
Phoenix. Using a second telescope, the star would be re-observed at the
frequency of the candidate ET signal. The rotation of the Earth produces a
distinct and different Doppler shift at the two telescopes. This technique,
called pseudo-interferometry, would rule out signals not coming from the
direction of the star. With this process and other tests, Project Phoenix has no
unresolved signals.
So after nine-plus years of bringing a complex system of electronics to
Australia, West Virginia, Georgia, England and Puerto Rico, Project Phoenix
is over. We observed more than a million star-MHz, processed millions of
signals, but found no evidence of another technological civilization in our
galactic neighborhood. Only one task remains, to write the papers for the
scientific journals. In the process of writing those reports, we also gather the
"lessons learned," an important part of preparing for the next search.
Years from now, Phoenix will be seen as humanity's first systematic survey of
the nearby stars. It was a major advance over all other SETI programs, but its
superlatives will not last. New, more powerful searches will be made in the
coming decades that will make the sensitivity, number of stars and frequency
coverage of Phoenix seem small in comparison. But, it will always be our
first big step in exploring our part of the Milky Way.
Read the original article at http://www.astrobio.net/news/article908.html.
There are two components to Cynthia's projects. One that I think is really
exciting is what she calls "change comparison." That goes back to her days of
being a graduate associate on the Galileo imaging team, where she did
comparisons to look for surface changes on another of Jupiter's moons, Io, and
was able to extend her comparisons to include older Voyager images of Io.
We have Galileo images of Io, taken in the late 1990s, and we have Voyager
images of Io, taken in 1979. So there are two decades between the two. If
you can do a faithful comparison of the images, then you can learn about
what's changed in the interim, get some sense of how geologically active the
world is. Cynthia did this comparison for Io, then did it for the much more
subtle features of Europa.
That may sound like a trivial task. And for really gross features I suppose it
is. You just look at the images and see if something's changed. But since the
Voyager camera was so different, since its images were taken at different
lighting angles than Galileo images, since the spectral filters were different,
there are all sorts of things that, once you get beyond the biggest scale of
examination, make that much more difficult than it sounds. Cynthia takes the
old Voyager images and, if you will, transforms them as closely as one can
into Galileo-type images. Then she overlays the images, so to speak, and does
a computer check for geological changes.
When she did this with Europa as part of her Ph.D. thesis, she found that there
were no observable changes in 20 years on those parts of Europa that we have
images for from both spacecraft. At least not at the resolution of the Voyager
spacecraft—you're stuck with the lowest resolution, say about two kilometers
per pixel. Over the duration of the Galileo mission, you've got at best five and
a half years. Cynthia's idea is that you're more likely to detect change in
smaller features, in a Galileo-to-Galileo comparison, at the much higher
resolution that Galileo gives you, than you were working with images that
were taken 20 years apart but that require you to work at two kilometers per
pixel. So she's going to do the Galileo-to-Galileo comparison.
The reason this is interesting from an astrobiological perspective is that any
sign of geological activity on Europa might give us some clues about how the
ocean and the surface interact. The other component of Cynthia's project is to
better understand the suite of processes involved in those interactions and
what their astrobiological implications might be.
AM: You and Kevin Hand are working together to study some of the
chemical interactions believed to be taking place on Europa. What
specifically will you be looking at?
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
CC: There are a number of components of the work I'm doing with Kevin.
One component stems from a paper that Kevin and I had in Science in 2001,
which has to do with the simultaneous production of electron donors and
electron acceptors. Life as we know it, if it doesn't use sunlight, makes its
living by combining electron donors and acceptors and harvesting the
liberated energy.
For example, we humans, like other animals, combine our electron donor,
which is reduced carbon, with oxygen, which is our electron acceptor.
Microbes, depending on the microbe, may use one, or several, of many
possible different pairings of electron donors and electron acceptors. Kevin
and I were finding abiotic ways that these pairings could be produced on
Europa, using what we understand about Europa now. Many of these are
produced through the action of radiation. We're going to continue that work
in much more detailed simulations.
We're also going to look at the survival potential of biomarkers at Europa's
surface. That is to say, if you're trying to look for biomarkers from an orbiter,
without getting down to the surface and digging, what sort of molecules
would you look for and what are your prospects for actually seeing them,
given that there's an intense radiation environment at the surface that should
slowly degrade them? Maybe it won't even be that slow. That's part of what
we want to understand. How long can you expect certain biomarkers that
would be revelatory about biology to survive on the surface? Is it so short that
looking from orbit doesn't make any sense at all, or is it long enough that it
might be useful?
That has to be folded into an understanding of turnover, or so-called "impact
gardening" on the surface, which is another component of my work with
Cynthia Phillips', by the way. Kevin will be getting at that by looking at
terrestrial analogs.
AM: How do you determine which biomarkers to study?
CC: There are certain chemical compounds that are commonly used as
biomarkers in rocks that go back billions of years in the terrestrial past.
Hopanes, for example, are viewed as biomarkers in the case of cyanobacteria.
These biomarkers withstood whatever background radiation was present in
those rocks from the decay of incorporated uranium, potassium, and so on, for
over two billion years. That gives us a kind of empirical baseline for
survivability of certain kinds of biomarkers. We want to understand how that
compares to the radiation and oxidation environment on the surface of Europa,
which is going to be much harsher.
10
NEW ADDITIONS TO THE ASTROBIOLOGY INDEX
By David J. Thomas
http://www.lyon.edu/projects/marsbugs/astrobiology/
6 April 2004
Astrobiology and planetary engineering articles
http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles1.html
H. Bortman, 2004. Europa: living world or frozen wasteland? An interview
with Christopher Chyba. Astrobiology Magazine.
Royal Astronomical Society, 2004. Life beneath the ice in the outer solar
system? SpaceDaily.
Terrestrial extreme environments articles
http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles2.html
C. Bakermans and K. H. Nealson, 2004. Relationship of critical temperature
to macromolecular synthesis and growth yield in Psychrobacter cryopegella.
Journal of Bacteriology, 186(8):2340-2345.
V. P. Edgcomb, S. J. Molyneaux, M. A. Saito, K. Lloyd, S. Böer, C. O.
Wirsen, M. S. Atkins and A. Teske, 2004. Sulfide ameliorates metal toxicity
for deep-sea hydrothermal vent archaea. Applied and Environmental
Microbiology, 70(4):2551-2555.
P. B. Price and T. Sowers, 2004. Temperature dependence of metabolic rates
for microbial growth, maintenance, and survival. Proceedings of the National
Academy of Sciences (USA), 101(13):4631-4636.
Human space exploration articles
http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles3.html
L. David, 2004. Moon-to-Mars feasible, experts say, but politics, lack of
industry cooperation could jeopardize vision. Space.com.
Royal Astronomical Society, 2004. Europe targets human exploration of the
Moon and Mars. SpaceDaily.
SETI articles
http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles4.html
P. Backus, 2004. Ashes of the Phoenix. Astrobiology Magazine.
Both Kevin and Max Bernstein are going to get after that question by doing
laboratory simulations. Max is going to be irradiating nitrogen-containing
biomarkers at very low temperatures in his laboratory apparatus, trying to
understand the survivability of the biomarkers and how radiation changes
them.
H. Bortman, 2004. Can intelligent life thrive in close quarters? An interview
with Christopher Chyba. Astrobiology Magazine.
S. Shostak, 2004. Cheap communication schemes for ET. Space.com.
AM: Because even if the biomarkers don't survive in their original form they
might get transformed into another form that a spacecraft could detect?
Evolution (biological, chemical and cosmological) articles
http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles5.html
CC: That's potentially the case. Or they might get converted into something
that is indistinguishable from meteoritic background. The point is to do the
experiment and find out. And to get a good sense of the time scale.
Georgia Institute of Technology, 2004. Molecular midwives hold clues to the
origin of life. SpaceDaily.
That's going to be important for another reason as well. The kind of terrestrial
comparison I just mentioned, while I think it's something we should know,
potentially has limits because any organic molecule on the surface of Europa
is in a highly oxidizing environment, where the oxygen's getting produced by
the radiation reacting with the ice. Europa's surface is probably more
oxidizing than the environment organic molecules would experience trapped
in a rock on the Earth. Since Max will be doing these radiation experiments in
ice, he will be able to give us a good simulation of the surface environment on
Europa.
Read the original article at http://www.astrobio.net/news/article909.html.
An additional article on this subject is available at
http://www.spacedaily.com/news/jupiter-europa-04c.html.
Extrasolar planets articles
http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles7.html
Royal Astronomical Society, 2004. How many habitable Earths are out there?
Universe Today.
Royal Astronomical Society, 2004. Hunt for extrasolar Earth-like planets
intensifies. SpaceDaily.
CASSINI SIGNIFICANT EVENTS
NASA/JPL release
25-31 March 2004
The most recent spacecraft telemetry was acquired from the Goldstone
tracking station on Monday, March 29. The Cassini spacecraft is in an
excellent state of health and is operating normally. Information on the present
position and speed of the Cassini spacecraft may be found on the "Present
Position"
web
page
located
at
http://jpl.convio.net/site/R?i=D0H_Amd62mxO-3BCLCXxIg.
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
11
and BISTAT Version 1.1 which incorporated atmospheric effects on the ray
path.
Science observations this week included Saturn approach movies to study the
planet's atmosphere and its temporal variations, searches for new satellites,
observations of Titan and searches for diffuse ring material, and solar wind
observations. The Magnetometer Subsystem performed a Science Calibration
Subsystem flight calibration, and commands were sent to the spacecraft to
power on the Cassini Plasma Spectrometer and perform Real Time Interrupt
testing.
Files for C44 were uplinked to the spacecraft this week. They included the
background sequence, instrument expanded blocks, and an absolute timed
Immediate/Delayed Action Program to perform an ACS Reaction Wheel
Assembly bias. C44 begins execution on Thursday, April 1. During C44 the
first time event "rocking downlink" will be performed for the Cosmic Dust
Analyzer (CDA). During the downlink, the spacecraft rolls about the Z-axis
in a back and forth manner. CDA will be performing rocking downlinks on
13 April.
Spacecraft Operations completed the Integrated Test Lab (ITL) dry run for the
ACS flight software update version A8.6.7 on Thursday, 4/1/04. The test was
important because this is the first time in flight an ACS computer will be reset
and loaded with a flight software update during an on-going background
sequence. The test was successful in that it did catch a missing vector needed
for the C44 background. The missing vector has been added and the test will
be re-run next week. Spacecraft Operations delivered version 10.3 of both
IVP and KPT. This is the planned tour version of these ground software tools.
The Sequence Team released the preliminary version of the S01 background
sequence and Phoebe Live Movable Block. Team members are in the process
of reviewing the integrated sequence.
In the last week, 265 Imaging Science Subsystem (ISS) images and 36 Visual
and Infrared Mapping Spectrometer (VIMS) cubes were returned and
distributed, bringing the total of images acquired since the start of Approach
Science up to 1969, and the number of cubes up to 663.
The Science Operations Plan Update process for S02, which includes the
science occurring during and after the Saturn Orbit Insertion burn, had its
official port 1 delivery this week. The team and engineering input products
were merged and the merged product was handed off to ACS to perform the
end-to-end pointing analysis. The S02 product will be handed off to the SSUP
process on April 9.
Tour Science Plan presentation #5 to the flight team this week was part 2 of
two parts on the Titan Orbiter Science Team plans for tour. This team was
responsible for integration of science activities for the 44 targeted Titan flybys
during the prime mission.
Delivery coordination meetings were held this week for Version 5.2 of
AP_DOWNLINK consisting of bug fixes and new telemetry predicts, version
10.3 of Kinematic Prediction Tool and Inertial Vector Propagator, and Radio
Science Subsystem tools LMBTRK Version 1.2 which incorporated the hardlimb approximation for faster calculations in the cases of large bending
angles, for which high accuracy is not needed, POSTLM Version 1.1 which
incorporated optimization and the capability to handle both ingress and egress,
As Cassini closes in on Saturn, its view is growing sharper with time and now
reveals new atmospheric features in the planet's southern hemisphere.
Atmospheric features, such as two small, faint dark spots, visible in the
planet's southern hemisphere, will become clearer in the coming months. The
spots are located at 38 degrees south latitude. The spacecraft's narrow angle
camera took several exposures on March 8, 2004, which have been combined
to create this natural color image. The image contrast and colors have been
slightly enhanced to aid visibility. Moons visible in the lower half of this
image are: Mimas (398 kilometers, or 247 miles across) at left, just below the
rings; Dione (1,118 kilometers, or 695 miles across) at left, below Mimas;
and Enceladus (499 kilometers, 310 miles across) at right. The moons had
their brightness enhanced to aid visibility. The spacecraft was then 56.4
million kilometers (35 million miles) from Saturn, or slightly more than onethird of the distance from Earth to the Sun. The image scale is approximately
338 kilometers (210 miles) per pixel. The planet is 23 percent larger in this
image than it appeared in the preceding color image, taken four weeks
earlier. [http://photojournal.jpl.nasa.gov/catalog/PIA05385]
A Delivery Review was held for the Multi Mission Image Processing
Laboratory point delivery D32.0.1. Testing results were reported and no
issues were brought up. Operations were then halted for a validation and
switchover period. This integrated system was then brought on-line as the
operational system for Tour.
New content and graphics were released to the Saturn Observation Campaign
website. Enhancements include compliance with the design features of the
NASA portal, new information, and announcement of application process for
new
SOC
members.
The
site
can
be
accessed
at
http://jpl.convio.net/site/R?i=IKbTaYcOmL1O-3BCLCXxIg.
Cassini Outreach is performed not only by members of the Outreach staff
located at JPL, but also by members of the flight team. A Radio and Plasma
Wave Science instrument team member gave a series of talks in his local
community to 22 first grade students at Weber Elementary School in Iowa
City as well as 15 members of a Girl Scout Troop in Iowa City. In addition, a
member of the Spacecraft Operations Office gave a talk to 21 3rd grade
students at Paradise Canyon Elementary School in La Canada.
Wind-blown clouds and haze high in Saturn's atmosphere are captured in a
movie made from images taken by the Cassini narrow angle camera between
February 15 and February 19, 2004. This is the first movie ever made
showing Saturn in these near-infrared wavelengths. The images were made
using a filter sensitive to a narrow range of wavelengths centered at 889
nanometers, where methane in Saturn's atmosphere absorbs sunlight. For
more information go to http://jpl.convio.net/site/R?i=CaW4WmTjYgVO3BCLCXxIg..IA05384.jpg&type=image
or
http://jpl.convio.net/site/R?i=3qsBGaLal0ZO-3BCLCXxIg.
In the week that sees the 375th anniversary of the birth of the Dutch
astronomer Christiaan Huygens, an international conference entitled "Titan:
From Discovery to Encounter" is taking place, from 13 to 17 April, at ESA's
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
European Space Research and Technology Centre (ESTEC), Noordwijk, the
Netherlands. The conference will bring together an international team of
space scientists and historians to discuss topics such as:

Christiaan Huygens and his connection with other 17th century
scientists, such as Cassini, Descartes and Newton;

observation of Saturn and its moons from the 17th century to today;

the scientific objectives of the Cassini/Huygens mission and its latest
observations on the way to the Saturnian system.
Cassini is a cooperative project of NASA, the European Space Agency and
the Italian Space Agency. The Jet Propulsion Laboratory, a division of the
California Institute of Technology in Pasadena, CA, manages the Cassini
mission for NASA's Office of Space Science, Washington, DC.
12
"The evidence is in the form of multiple coatings on the rock, as well as
fractures that are filled with alteration material and perhaps little patches of
alteration material," McSween said during a press conference at NASA's Jet
Propulsion Laboratory, Pasadena, CA.
The rock, called "Mazatzal" after mountains in Arizona, lies partially buried
near the rim of the crater informally named "Bonneville" inside the much
larger Gusev Crater. Its light-toned appearance grabbed scientists' attention.
After Spirit's rock abrasion tool brushed two patches on the surface with wire
bristles, a gray, darker layer could be seen under the tan topcoat. The rock
abrasion tool ground into the surface with diamond cutting teeth on March 26.
Then, after an examination of the newly exposed material, it ground deeper
into the rock two days later. A lighter-gray interior lies under the darker layer,
and a bright stripe cuts across both.
Additional articles on this subject are available at:
http://www.astrobio.net/news/article905.html
http://www.space.com/scienceastronomy/cassini_closer_040402.html
http://www.spacedaily.com/news/cassini-04c.html
http://spaceflightnow.com/news/n0404/02saturnspots/
MARS EXPLORATION ROVERS STATUS REPORTS
NASA/JPL releases
Spirit Finds Multi-Layer Hints of Past Water at Mars' Gusev Site
NASA/JPL release 2004-093, 1 April 2004
Clues from a wind-scalloped volcanic rock on Mars investigated by NASA's
Spirit rover suggest repeated possible exposures to water inside Gusev Crater,
scientists said Thursday. Gusev is halfway around the planet from the
Meridiani region where Spirit's twin, Opportunity, recently found evidence
that water used to flow across the surface.
This image was taken by the Mars Exploration Rover Spirit's panoramic
camera during the rover's grinding of the rock dubbed "Mazatzal" with its
rock abrasion tool. The picture shows the rock after the rover drilled 3.8
millimeters (.15 inches) into the target dubbed "New York" on Sol 82. The
dark grey coating seen after brushing remains on the right side of the hole,
while the left side is the underlying basaltic rock. This approximate truecolor image was created using the panoramic camera's red, green and blue
filters. Image credit: NASA/JPL/Cornell.
Dr. Jeff Johnson, a science team member from the U.S. Geological Survey's
Astrogeology Team, Flagstaff, AZ, said the stripe "seems to be a fracture that
water has flowed through, potentially with minerals precipitating from that
fluid and lining the walls of the crack."
He and other scientists stressed that the interpretations are preliminary. "The
team is, as always, trying to find time to digest these observations while also
preparing for the next day's operations," Johnson said.
This approximate true-color image taken by the panoramic camera on the
Mars Exploration Rover Spirit shows the rock dubbed "Mazatzal" before the
rover drilled into it with its rock abrasion tool. On sol 82, Spirit ground into
a circular patch of the rock called "New York," then repeated this operation
on sol 85 to complete the hole. Several observations were made during this
grinding process with the rover's suite of scientific instruments. Preliminary
results suggest that fluid may have been present during Mazatzal's formation.
Images from the panoramic camera's blue, green and red filters (480, 530 and
600-nanometer filters) were combined to make this picture. Image credit:
NASA/JPL/Cornell.
"This is not water that sloshed around on the surface like what appears to have
happened at Meridiani. We're talking about small amounts of water, perhaps
underground," said Dr. Hap McSween, a rover science team member from the
University of Tennessee, Knoxville.
Spirit's alpha particle X-ray spectrometer checked what chemical elements
were close to the surface of untreated, brushed, once-drilled and twice-drilled
patches. "Miracles, miracles, miracles. We have a lot of work to do," the
instrument's lead scientist, Dr. Rudi Rieder of the Max Planck Institute,
Mainz, Germany, exclaimed about the results. For example, the ratio of
bromine to chlorine seen inside the rock is unusually high and possibly a clue
to alteration by water.
The final experiment on Mazatzal was to scrub the surface with the rock
abrasion tool in a pattern of five circles arranged in a ring, with a sixth circle
in the center. Besides creating a rock-art daisy, this task by the engineers of
New York-based Honeybee Robotics, as well as JPL, produced a brushed
patch big enough to fill the field of view of Spirit's miniature thermal emission
spectrometer, said Dr. Steve Ruff of Arizona State University, Tempe. The
tan outer surface appears to have a strikingly different mineral composition
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
than the dark gray coating exposed by the brushing, but more time is needed
to complete the analysis, he said.
McSween proposed that the light outer coat, dark inner coat and bright veins
could have resulted from three different periods of the rock being buried,
altered by fluids and unburied.
While scientists await transmission of additional data Spirit has collected
about Mazatzal, the rover will be making its way toward the "Columbia Hills"
about 2.3 kilometers (1.3 miles) away. Spirit left the rock and drove 36.5
meters (120 feet) early Thursday.
13
bounce marks show that the spacecraft hit it on landing day two months ago.
"We're looking to break that record again very soon with longer and longer
drives," said JPL's Chris Lewicki, flight director.
Before moving on across the plains of Meridiani, though, Opportunity will
complete an investigation it has begun of Bounce Rock. The rock is unlike
any seen on Mars before, said Dr. Jim Bell, lead scientist for the rovers'
panoramic cameras. "There are some shiny surfaces on this rock," he said,
describing them as "almost mirrorlike."
The two rovers' 18 cameras have now taken more than 20,000 images.
NASA's Mars Success Honored at Disney World Day of Discovery
NASA release 04-114, 6 April 2004
NASA Administrator Sean O'Keefe joins NASA scientists, mission managers
and a Mars rover today to help Disney's Epcot, at the Walt Disney World
Resort, celebrate the success of the Mars Exploration Rovers Spirit and
Opportunity. The Administrator's now famous quote, "We're back... and
we're on Mars" is being added to a permanent collection of space-related
quotations on the façade of Disney's latest attraction, "Mission: SPACE." The
popular attraction launches visitors on a simulated space adventure to the Red
Planet. "Mission: SPACE" combines NASA-based technology and imagery
with the creative minds of Walt Disney Imagineering to deliver a one-of-akind exploration experience.
"The attraction builds on a foundation of science fact and provides visitors a
fantasy ride into the future of exploration," said Administrator O'Keefe. "It's a
realistic experience that can introduce a new generation of explorers to the
excitement of science, technology and discovery."
This Mars Exploration Rover Opportunity panoramic camera image shows
"Bounce Rock," a rock the airbag-packaged rover struck while rolling to a
stop on January 24, 2004. This is the largest rock for as far as the eye can
see, approximately 35 centimeters (14 inches) long and 10 centimeters (4
inches) high. There appears to be a dusty coating on the top of parts of the
rock, which may have been broken when it was struck by the airbags. The
rock was about 5 meters (16 feet) from the rover when this image was
obtained. This is an enhanced color composite image from sol 36 of the
rover's journey, generated using the camera's L2 (750 nanometer), L5 (530
nanometer), and L6 (480 nanometer) filters.
Image credit:
NASA/JPL/Cornell.
"Mission: SPACE" officially opened October 9, 2003. It is Disney's most
technologically advanced attraction, relying on visual imaging, motion control
and centrifuge technology to send would-be astronauts on a futuristic voyage.
"Mission: SPACE appeals to the explorer in all of us," said Al Weiss,
president of Walt Disney World Resort, Lake Buena Vista, Fla. "NASA's
triumphant Mars missions embody that spirit of exploration. We are pleased
and honored to have Administrator O'Keefe's comments taking their place at
Mission: SPACE alongside those of others who dared to dream," he said.
NASA provided Disney's Imagineering team with tours, briefings and
discussions about human and robotic missions, as well as the challenges future
missions, like a trip to Mars, might present. The attraction took five years and
some 350,000 work-hours to build.
During a special ceremony, an actual Mars rover made a ceremonial pass
through wet cement. Administrator O'Keefe's quote will be affixed near the
rover's tracks in the attraction's planetary courtyard. The latest developments
and discoveries on Mars also were shared during the event.
As for the real rovers traversing Mars some 300 million miles from Earth,
Spirit and Opportunity have made extraordinary discoveries and found
important clues to a watery past on the martian surface. The Spirit rover is
driving toward the "Columbia Hills," and Opportunity has been making close
examinations of a martian rock known as "Bounce" before moving toward
Endurance Crater.
For information about the latest developments on Mars and Disney's
"Mission: SPACE" attraction on the Internet, visit:
http://www.nasa.gov/vision/universe/solarsystem/mer_main.html
http://disney.go.com/vacations/missionspace/ms_mainflash.html
For information about NASA and agency missions on the Internet, visit
http://www.nasa.gov.
This high-resolution panoramic camera blue filter image of the rock dubbed
"Bounce" was obtained up close, just before the rover placed its instruments
on the rock for detailed study. The rock has a number of shiny surfaces and
textures on it, some of which are unlike those seen in the Eagle Crater rock
outcrop. Also, the rock was apparently moved or shaken when it was hit with
the airbags, as can be seen by the gap and cracks in the soil around the rock.
This image from sol 65 of the rover's journey was acquired using the
panoramic camera's 430 nanometer filter. Image credit: NASA/JPL/Cornell.
Opportunity set a one-day driving record on Mars on March 27 by covering
48.9 meters (160 feet) toward a rock called "Bounce Rock" because airbag
JPL, a division of the California Institute of Technology in Pasadena, manages
the Mars Exploration Rover project for NASA's Office of Space Science,
Washington, DC. Images and additional information about the project are
available from JPL at http://marsrovers.jpl.nasa.gov, and from Cornell
University, Ithaca, NY, at http://athena.cornell.edu.
Daily MER updates are available at:
http://marsrovers.jpl.nasa.gov/mission/status_opportunity.html
http://marsrovers.jpl.nasa.gov/mission/status_spirit.html
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
14
Contacts:
Guy Webster
Jet Propulsion Laboratory, Pasadena, CA
Phone: 818-354-5011
cap to grow in size (as atmospheric carbon dioxide freezes onto the pole) and
cover some of the permafrost region.
Donald Savage
NASA Headquarters, Washington, DC
Phone: 202-358-1547
The summit caldera of Hecates Thous, the largest volacno in the Elysium
volcano group. The caldera shows multiple collapses caused by the emptying
of the underlying magma chamber. On the sides of the volcano there is
evidence for lava flow features.
Additional articles on this subject are available at:
http://www.astrobio.net/news/article906.html
http://www.space.com/marsrover/
http://www.spacedaily.com/news/mars-mers-04zzzo.html
http://spaceflightnow.com/mars/mera/040401status.html
http://www.universetoday.com/am/publish/spirit_hints_past_martian_water.ht
ml
MARS EXPRESS: COMMISSIONING ALMOST COMPLETE
ESA release
1 March 2004, HRSC: Hecates Tholus
Read
the
original
news
release
e/www/object/index.cfm?fobjectid=34898.
at
http://sci.esa.int/science-
Additional articles on this subject are available at:
http://www.spacedaily.com/news/marsexpress-04j.html
http://www.spacedaily.com/news/mars-life-04a.html
http://www.spacedaily.com/upi/20040331-17482700.html
MARS GLOBAL SURVEYOR IMAGES
NASA/JPL/MSSS release
31 March 2004
25-31 March 2004
Since the last status report, the overall operational performance of the
spacecraft and payload continued to be satisfactory. Some temporary
problems were encountered with the Solid State Mass Memory (SSMM),
which are currently under investigation. Remaining payload-commissioning
activities are being performed until mid-April. The MARSIS radar will be
deployed on 20 April and subsequently the spacecraft will be fully
commissioned. Spacecraft resources, in particular power usage, are still
constrained as Mars Express has encountered the first eclipse season, although
the duration of eclipses per orbit is now slowly decreasing every day.
The following new images taken by the Mars Orbiter Camera (MOC) on the
Mars Global Surveyor spacecraft are now available.
Craters and Wind Streaks (Released 25 March 2004)
http://jpl.convio.net/site/R?i=sNxOv_cbM4NO-3BCLCXxIg
Russell Dunes (Released 26 March 2004)
http://jpl.convio.net/site/R?i=681QkPwcAptO-3BCLCXxIg
The status and performance of the orbiter payload in Mars orbit is excellent,
with new high-resolution stereo and colour images and high-resolution
spectral measurements of the planet being acquired, and further radio science
data collected. The orbit of the Mars Express spacecraft continues to be very
stable. Imaging instruments and spectrometers have begun global coverage
science data acquisition. In particular, HRSC and OMEGA have started to
perform mosaic and map construction. Since the last status report the
following science material has been released.
South Polar Layers (Released 27 March 2004)
http://jpl.convio.net/site/R?i=XTT8D_n7_pJO-3BCLCXxIg
30 March 2004, PFS: Evidence of Methane
Crater in Cydonia (Released 30 March 2004)
http://jpl.convio.net/site/R?i=fMPh-X9krCFO-3BCLCXxIg
Observations by the PFS instrument indicate that methane is present in the
martian atmosphere. The measurements so far suggest that the amount of
methane present is about 10 parts per billion.
22 March 2004, HRSC: Ascraeus Mons
The image reveals formations, associated with volcanic activity, that have also
been witnessed on Earth, and elsewhere in the Solar System. The lava tubes
are caused by crusting which occurs over a lava channel, effectively turning it
into a tunnel. If the tunnel empties of all its lava then it will collapse and
leave depression on the planetary surface.
17 March 2004, OMEGA: Water Evidence Confirmed
Further analysis of OMEGA measurements at the martian south pole have
confirmed the presence of water ice. The majority of the water ice is in a
permafrost region surrounding the central polar cap. The composition of this
region is thought to be 15% water ice and 85% carbon dioxide ice. The
measurements were made between 18 January and 11 February 2004—when
summer was coming to an end at the southern cap. This meant the polar cap
was at its smallest extent. In the coming months scientists expect the polar
Layered South Polar Slope (Released 28 March 2004)
http://jpl.convio.net/site/R?i=pS0ZFnJmCZ1O-3BCLCXxIg
Gullies With Bright Material (Released 29 March 2004)
http://jpl.convio.net/site/R?i=AJhOZ3zAkb1O-3BCLCXxIg
West Candor Layers (Released 31 March 2004)
http://jpl.convio.net/site/R?i=liBallDLR4tO-3BCLCXxIg
All of the Mars Global Surveyor images are archived at
http://jpl.convio.net/site/R?i=nAkxphoQSs5O-3BCLCXxIg.
Mars Global Surveyor was launched in November 1996 and has been in Mars
orbit since September 1997. It began its primary mapping mission on March
8, 1999. Mars Global Surveyor is the first mission in a long-term program of
Mars exploration known as the Mars Surveyor Program that is managed by
JPL for NASA's Office of Space Science, Washington, DC. Malin Space
Science Systems (MSSS) and the California Institute of Technology built the
MOC using spare hardware from the Mars Observer mission. MSSS operates
the camera from its facilities in San Diego, CA. The Jet Propulsion
Laboratory's Mars Surveyor Operations Project operates the Mars Global
Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics,
from facilities in Pasadena, CA and Denver, CO.
End Marsbugs, Volume 11, Number 15.