Project Title: Shoemaker-Levy 9 Data

Project Description:

  1. Reduce and analyze astronomical data on Jupiter from and subsequent to the Shoemaker-Levy 9 impact period. These data are in both an imaging and spectroscopic form. Physical quantities to be retrieved will include temperatures, cloud properties, and gas composition. Extensive use of FORTRAN and IDL (Interactive Data Language, a FORTRAN-like programming language).
  2. articipate in modelling the convergence of radiant flux in the atmosphere of Jupiter which emerges from thermal sources. These models will be used as the basis for continuing studies of the temporal and vertical variability of Jupiter's temperature structure and circulation system. The results will be compared with the observed time variability of Jupiter over several years and over the several days subsequent to the perturbations by the Shoemaker-Levy-9 fragment bombardments. They will also form the basis of models to be compared with the data returned from the Galileo (Jupiter) Probe Net Flux Radiometer experiment after the December 9, 1995, Probe entry into Jupiter's atmosphere.

Background Information:

The bombardment of Comet Shoemaker-Levy 9 with Jupiter left a legacy of several Gigabytes of astronomical data taken by the sponsor, his colleagues and collaborators. Only the very first results of these observations have been published, with the bulk of the data from various observatories, including the Hubble Space Telescope Wide-Field and Planetary Camera (WF/PC) remaining for making detailed quantitative descriptions of the state of the atmosphere at the time. The results of the models often also include a description of the equatorial region into which the Galileo Probe will make direct atmospheric measurements for the first time in early December of 1995. The data taken in the summer of 1994 and the subsequent observations of the aftermath provide the best opportunity to make the latest updates to the state of the atmosphere from various remote sensing observations. This portion of the opportunity will involve extensive data reduction, including upgrading a general program for data reduction - DRM (Data Reduction Manager) - written by the sponsor and previous students.

The observations of the Galileo Net Flux Radiometer will provide a direct means of testing our assumptions about the properties of clouds, gas distributions and temperatures in Jupiter's atmosphere. Calculation of these fluxes in the context of a baseline model for the atmosphere and perturbations to temperatures, gas abundances and cloud properties will be done in order to create a quick means to assess the meaning of the NFR data after it is received. The determination of these fluxes also provides the basis for radiatively and convectively driven models of seasonal and non-seasonal time dependences of temperatures in the atmospheres of Jupiter and the other outer planets which can be compared directly with many years of observations, and they cam be compared with the shorter-term perturbation of temperatures after the SL9 fragment bombardments and their rapid re-equilibration which may have been accomplished by radiative decay of a highly enriched field of particulates in the impact environment - "dust' remaining from the impactor itself or re-condensed from material upwelled from the warmer deep atmosphere to the colder upper atmsosphere. This part of the opportunity will involve only secondary references to the data, and will be constituted primarily of FORTAN-based numerical simulations of the transfer of radiation in Jupiter's atmosphere.

Literature References:

  1. Current scientific publications on the Shoemaker-Levy 9 observational results few, outside the popular literature. As of this date (Dec. 15), several papers have been submitted to Science (Hammel et al. on Hubble imaging results, Orton et al. on a summary of the NASA Infrared Telescope Facility results, Martin et al. on the Galileo Photopolarimeter-Radiometer results), and to Geophysical Research Letters for a special SL9 issue (Carlson et al. on Galileo Near-Infrared Mapping Spectrometer results, and many, many other results from ground-based observatories). Prediction models are given in an earlier 1994 special issue of GRL (Vol. 21), others are: Zahnle and MacLow (1994) Icarus 108, 1; Harrington et al. (1994) Nature 368, 525; Boslough et al (1994) EOS 75, 305; Takata et al. (1994) Icarus 109, 3.
  2. An introduction and general explanation of the Galileo mission are given in the Space Science Reviews Volume 60, Nos. 1-4; a specific description of the NFR experiment is given in the article by Sromovsky et al. on page 233 of this Space Science Review issue.

Requirements:

The sponsor requires that interested students meet the following requirements: The applicant should feel free to contact earlier SURF students regarding their experiences in similar research:

This opportunity is for:

Caltech students. Will consider non-Caltech students

Research Sponsor

Sponsor: GLENN S. ORTON
Division: JPL
Mail Code: 169-237
Phone: 818-354-2460
(FAX) 818-393-4619
E-mail: go@orton.jpl.nasa.gov

For further information about the project, the student should contact: Glenn Orton (go@orton.jpl.nasa.gov), James Friedson (ajf@maui.jpl.nasa.gov), Padma Yanamandra-Fisher (padma@lono.jpl.nasa.gov)