Cover Page/Proposal Summary

ROSS-99    NRA 99-OSS-01

Date Due: 5/3/99

NASA PROCEDURE FOR HANDLING PROPOSALS

This proposal shall be used and disclosed for evaluation purposes only, and a copy of this Government notice shall be applied to any reproduction or abstract thereof. Any authorized restrictive notices that the submitter places on this proposal shall also be strictly complied with. Disclosure of this proposal for any reason outside the Government evaluation purposes shall be made only to the extent authorized by the Government.

Confirmation # 00-030   Date Received: Apr 20, 1999

Proposal Type: New Proposal

Proposal Category: Comets

Major Equipment Proposal? No

Do you intend to submit an Education/Public Outreach (E/PO) proposal? No

Proposal Title:
The Distribution of Gases in the Inner Comae of Comets

Abbreviated Proposal Title:
Gas Comae of Comets

Principal Investigator:
Dr. Michael R. Combi
Atmos., Oceanic, and Space Sciences Space Physics Res. Lab.
University of Michigan
2445 Hayward Street
Ann Arbor, MI 48109-2143
Phone: 734-764-7226   Fax: 734-647-3083   E-mail: mcombi@umich.edu

SignatureDate
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Co-Investigators and Collaborators:
Type    Name    Affiliation    E-mail
Sci Collab   Dr. Uwe Fink   University of Arizona   uwefink@lpl.arizona.edu
Sci Collab   Dr. Walter Harris   University of Wisconsin   wharris@sal.wisc.edu
Sci Collab   Dr. Frank Scherb   University of Wisconsin   scherb@wisp..physics.edu
Sci Collab   Dr. Fred Roesler   University of Wisconsin   roesler@wisp.physics.wisc.edu
Sci Collab   Dr. Christopher Anderson   University of Wisconsin   anderson@astro.wisc.edu
Sci Collab   Dr. Dominique Bockelee-Morvan   Observatoire de Meudon Paris   domi@mesioa.obspm.fr
Sci Collab   Dr. Tamas Gombosi   University of Michigan   tamas@umich.edu


Proposal Summary:

In order to understand the physical and chemical processes which produce the observed spatial morphology of the cometary coma, it is necessary to analyze observational data with physically meaningful models. With this in mind, the purpose of this project is to undertake a coupled and complementary program of theoretical modeling and observational data analysis regarding the spatial distributions and dynamics of neutral and ionized gases in the coma. The emphasis of theoretical modeling will be on the non-equilibrium dynamics of the inner coma from the fluid region through the transition from collisional fluid-flow to the free-flow region with specific emphasis on observable conditions in the coma. For observational data analysis we will use the various powerful modeling tools we have developed and have available, including hydrodynamics, MHD, Monte Carlo, Direct Simulation Monte Carlo and various hydbrid calculations. The analysis of observational data will involve new and fruitful ongoing collaborations with groundbased programs, as well as any data of opportunity which might become available.