8008(  1) - 04/16/98 14:17  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      8008
                                                       Version: 1
                                                       Check-in Date: 16-Apr-1998
                                                                      14:13:10

1.Proposal Title:
Analysis of FOS Spectra of Jupiter with a Raman Scattering Model
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2. Proposal For  3. Cycle
AR               7
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4. Investigators
                                                                                     Contact?
    PI: Dr. Roger Yelle                   Boston University
   CoI: Dr. Melissa McGrath               Space Telescope Science Institute             N
   CoI: Yan Betremieux                    Boston University                             N

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5. Abstract

We propose to analyze FOS G190H spectra in the HST archive in order to determine the
abundance of C_2H_2, NH_3, aerosols, and possibly other absorbers. The distribution
of absorbing species with latitude and longitude will be determined by examination
of spectra from a wide range of geographic locations. Examination of the HST archive
reveals more than 40 FOS G190H spectra covering all latitudes in the northern and
southern hemispheres and a wide range of longitudes. The spectra will be analyzed
with a radiative transfer model for the scattering of light in Jupiter's atmosphere.
This model is unique because it accurately incorporates the effects of Raman
scattering. We present calculations which show that inclusion of Raman scattering
greatly increases the quality of information that can be obtained from the FOS
spectra. We demonstrate that many of the features considered by earlier analyses to
be artifacts of the data reduction process are in fact Raman ghosts of solar
spectral lines. This implies that the noise level in the data is much smaller than
previously believed and, as a consequence, it should be possible to more tightly
constrain the abundance of aerosols and gaseous absorbers. We have detected both
vibrational and rotational Raman features. The existence of rotational Raman
features raises the possibility that the H_2 ortho/para ratio can be determined from
UV spectra.
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  Data Distribution

  Media:           ELECTRONIC
  Blocking Factor: 10
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                                                8008(  1) - 04/16/98 14:17  - [  2]

            Summary Form for Proposal  8008

  Item                         Used in this proposal
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  Proposal Category            AR
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