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Astrobiology related science
at STScI
Solar system observations
HST and planetary transits
HD 209458 – discovered by Keck/Geneva RV teams
- transit detected by Charbonneau et al (2000)
using ground-based photometry
HST data
provide
unparallelled
photometric
accuracy
STScI and transit surveys
Kepler – photometric survey of
105 solar-type stars in Cygnus
search for transits by jovian
and terrestrial planets
HST and planetary masses
All current planetary-mass companions
have been identified based on
radial velocity variations.
 orbital inclination not known, so
we can only derive M sin(i)
Are they really planetary-mass objects?
HST can provide the
precision astrometry
required to determine i
Positional residuals < 0.3 mas set upper limit of 30 MJ
Coronography with HST
NICMOS: IR
dusty disks around
nearby stars
Ring-like structures
probably indicate
the presence of
planetary-mass bodies
Coronography with HST
• ACS Stellar
Coronograph
– high contrast imaging
Flux Arcsec -2 (relative to total stellar flux)
– planets/low mass stars
– dust disks
– galaxies around quasars
10
-2
1.8" Spot Azimuthal Median Profiles
F435W
F814W
10-4
Direct (no coronagraph)
10-6
Coronagraph only
10-8
Coronagraph - star
10
-10
Sparks, Clampin
0
2
4
Arcsec
6
8
Coronography: The next step
Jovian Planet Finder:
Clampin et al
TPF:
R. Brown et al
Optical coronography
Brown dwarfs at STScI
Brown dwarfs serve as a bridge
to studying atmospheres of
giant planets
High spatial resolution
permits identification
of low-mass binaries
2M0850+1057
60 MJ + 55 MJ
The Galactic distribution
What parameters drive planet formation?
Metallicity
1. No planets detected in
47 Tucanae
2. Clear preference for
high metallicities
amongst known systems
James Webb ST
Three science instruments:
1. MIRI – mid-infrared imaging and spectroscopy
5  28 m Protostellar disks, planet formation
2. NIRCAM – near-infrared imaging, 0.6 5 m
brown dwarfs, low-mass companions
3. NIRSPEC – near-infrared spectroscopy, 0.6 5 m
low temperature atmospheric parameters