11239(  1) - 03/30/07 11:00  - [  1]

                  HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 11239

Version: 1    Check-in Time: 30-Mar-2007 15:00:10       STScI Edit Number: 0

Title
Identifying Atomic and Molecular Absorption in an Extrasolar Planet Atmosphere
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Type             Cycle     Parallel Pointing Tolerance
AR               16        <none>
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Investigators
                                                                                     Contact?
    PI: Dr. Travis Stuart Barman          Lowell Observatory

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Abstract

A significant amount of Hubble Space Telescope time has been spent observing a
normal bright main-sequence star, HD209458, which happens to also be home to one of
the few transiting extrasolar planets. Time-series spectroscopic data taken with
STIS and ASC are available in the archive covering numerous planetary transits over
the past 7 years. These data have allowed the discovery of sodium absorption in
HD209458b's atmosphere along with a hydrogen-rich extended exosphere. There is great
potential for significant new discoveries with these data that could further
constrain the chemical composition and chemical evolution of HD209458b. This
proposal outlines steps toward improving our understanding of the chemical
composition of extrasolar giant planet atmospheres by developing new models for the
wavelength-dependent eclipse depth that may be directly compared to archival Hubble
Space Telescope observations.
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