Hubble Space Telescope
Cycle 11 General Observer Proposal
The Next Step in Exoplanet Research
Principal Investigator: Mr. Drew Ciampa
Institution: Stony Brook University
USA/NY
Electronic mail: Drew.Ciampa@stonybrook.edu
Scientific category: SOLAR SYSTEM
Scientific keywords: PLANETARY ATMOSPHERES, EMISSION LINES,
CHEMICAL ABUNDANCE, SPECTROSCOPY, SURVEY
Instruments: WFC3 Proprietary period: 0
Cycle 11 primary orbits: 7
Cycle 11 parallel orbits: 0
Abstract
We’re now in the age of not only discovering exoplanets which find themselves in the
habitable zone, but also discovering the exoplanets that contain water. Using some of the
newest equipment on the Hubble Space Telescope such as The Wide Field Camera 3, WFC3,
I plan to take the infrared spectrograph of the exoplanets which have been regarded as the
most likely water bearers.
The spectrograph should not only provide us with a detailed spectrum of the planets,
but it will also give us plenty of information on the planets atmosphere, chemical abundances,
and ultimately the likelihood that the planet contains water. Having the spectrograph will
alow us to understand some of the major properties behind planetary conditions.
In all, this program should enable us to further detail exoplanets and their properies.
It will give us the ability to categorize exoplanets according to more than just their size and
distance from the mother star.
Mr. Drew Ciampa
The Next Step in Exoplanet Research
Investigator
PI: Mr. Drew Ciampa
Total number of investigators:
Observing Summary:
Target
RA
GLIESE-667C 17 18 57
C
Institution
Stony Brook University
Country
USA/NY
1
DEC
-34 59 23
GLIESE-667C 17 18 57
F
-34 59 23
GLIESE-667C 17 18 57
E
-34 59 23
KEPLER-22B
19 16 52
+47 53 04
KEPLER-62E
18 52 51
+45 20 59
KEPLER-62F
18 52 51
+45 20 59
KEPLER-61B
19 41 13
+42 28 31
V
Configuration,mode,aperture
spectral elements
WFC3 IR SPECTROSCOPY
GRISM1024, IR
MULTIACCUM
WFC3 IR SPECTROSCOPY
GRISM1024, IR
MULTIACCUM
WFC3 IR SPECTROSCOPY
GRISM1024, IR
MULTIACCUM
WFC3 IR SPECTROSCOPY
GRISM1024, IR
MULTIACCUM
WFC3 IR SPECTROSCOPY
GRISM1024, IR
MULTIACCUM
WFC3 IR SPECTROSCOPY
GRISM1024, IR
MULTIACCUM
WFC3 IR SPECTROSCOPY
GRISM1024, IR
MULTIACCUM
Grand total orbit request
2
Total
orbits
1
1
1
1
1
1
1
7
Flags
Mr. Drew Ciampa
The Next Step in Exoplanet Research
Scientific Justification
For nearly the past 20 years, astronomers have been fascinated with finding the next Earth.
This fascination has led to the discovery of thousands of exoplanets. Many of these exoplanets
cannot sustain life with how close or far they are from their central star. But there are the
few who posess the proper position where life may exist. This distance from their star is
known as the habitable zone. The planets found here are extremely important to finding life
in the universe outside of our solar system. Recently, the interest in exoplanets has dwarfed
the astronomy community and has spread to everyday conversation. Conversations, between
all types of people, now include exoplanets and life on other planets. Not only has this given
incentive to find water capable of sustaining life on another planet, but it also has shown
the importance of astronomy in the world today.
Of all the exoplanets discovered in the habitable zone, 7 were chosen as the best-fit.
Gliese-667C c, Gliese-667C f, Gliese-667C e, Kepler-22b, Kepler-61b, Kepler-62e, and Kepler62f. I chose these planets because of their preferable properties that we have measured thus
far. From previous studies we see that these planets have ESI (Earth Similarity Index)
relatively close to Earth (1). They also have very accommodating HZA (Habitable Zone
Atmosphere) numbers. This was important for me to take into account with this study
because I plan on discovering the atmospheres of the planets and from that determining the
composition and chemical abundances. When selecting the planets the aspect of diversity
came into play. It’s great to pick planets which seem very earthlike, but using a planet which
differs in some special way may actually expand our knowledge about life outside of Earth.
With these 7 planets, monumental leaps can be made in our knowledge of exoplanets
and their dynamics. By measuring the spectrum of these planets the abundance ratios can
be determined using absorption/emission lines in the spectrum. Through this we can see
what type of atmosphere these planets have and what type of world it may be host to. The
components and properties of an atmosphere are crucial to any progression in the field. The
atmosphere contains molecules that can tell us whether water is present in the environment.
With water present, we make some of the most substantial finds in astronomy. Having water
makes the chance of life on that planet go up exponentially.
Astronomy needs to take the next step in the search for life in the universe. This program
takes that next step. We have the chance to categorize exoplanets by their atmosphere and
chemical compositions. With that we can find which planet is likely to have water. Nothing
of the sort has been researched, and with this proposed program, we can discover things
people have only dreamed about. Finding water on exoplanets is essential to finding life
outside our solar system. This is a major and necessary step in astronomy today.
Description of the Observations
The aperature that will be used for this program is the GRISM1024 full frame aperature.
The GRISM (Grating PRISM) provides us with slitless spectroscopy in the Infrared. GRISM
has two channel filters that will be utilized, these are the Blue high resolution and Red low
resolution channel filters. The Blue and Red channel filters will span from 800-1150nm
3
Mr. Drew Ciampa
The Next Step in Exoplanet Research
and 1175-1700nm,respectively. With this equipment we should be able to record a detailed
spectrograph of the planet.
The estimation of exposure time was calculated by using table 7.8 proved in section
7.7.3 fo the WFC3 Instrument Handbook. For this we took into account the S/N ratio we’d
want to achieve, which was 15. Next the objects brightness was consided, obviously being a
planet this would be extremely faint. Therefore a longer exposure would be necessary. This
led to using the STEP400 NSAMP14. This would provide us with 40 minute exposures.
For this program, 7 orbits are requested. We have 7 planets to investigate and with each
planet we have estimated a time of 55 minutes will be used on each planet. The following
table shows you how time will be used in one orbit.
Action
Guide-star acquisition
IR overheads
Science exposure(undispersed)
Science exposure(GRISM)
Total time used
Time(Minutes)
6.0
3 x 1.0 = 3.0
2 x 2.3 = 4.6
40
53.6
Summary
Required at start of observation.
STEP25 NSAMP15
STEPS400 NSAMP14
Looking at this you see that nearly one observation of a planet takes around 55 minutes.
With 7 different planets to observe we’d need 7 orbits to satisfy one observation per planet.
A STEP sequence is necessary because of the difference in brightness between the planet and
the star. STEP sequences produce a logarithmic sequence which helps produce an image
for the fainter object. The guide-star aquisition is something that must be done for each
observation. The undispersed science exposure is crucial. That image is used to calibrate
the position and wavelengths.
Special Requirements
Coordinated Observations
Justify Duplications
Previous HST Programs
4