00-098

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.

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 composition and heliocentric dependence of organics in comet Hyakutake

Abbreviated Proposal Title:
Organics in comet Hyakutake

Principal Investigator:
Dr. Michael Mumma
Lab. for Extraterrestrial Physics Mail Code 690
NASA's Goddard Space Flight Center
Buiding 2 Room 150
Greenbelt, MD 20771
Phone: 301-286-6994   Fax: 301-286-0212   E-mail: mmumma@lepvax.gsfc.nasa.gov

SignatureDate
_________________________________________________

Co-Investigators and Collaborators:
Type    Name    Affiliation    E-mail
Sci Co-I   Dr. Neil Dello Russo   GSFC and Catholic University   ysndr@lepvax.gsfc.nasa.gov
Sci Co-I   Dr. Michael A. DiSanti   GSFC and Catholic University   disanti@kuiper.gsfc.nasa.gov
Sci Co-I   Dr. Karen Magee-Sauer   Rowan University   sauer@rowan.edu
Sci Co-I   Dr. Dennis C. Reuter   Code 693, NASA Goddard Space Flight Center   u3dcr@lepvax.gsfc.nasa.gov


Proposal Summary:

We acquired several thousand spectra of comets Hyakutake and Hale-Bopp, using CSHELL at the NASA Infrared Telescope Facility. Quick-look results were published for Hyakutake, and in-depth analyses are now being published for Hale-Bopp. This proposal requests funding to conduct in depth spectral analysis of organics in comet Hyakutake. We will use data algorithms developed and proved during our reductions of Hale-Bopp spectra. We will develop improved (nu2, nu3, nu9) fluorescence models for methanol and an improved model for methane (nu3). We will obtain extended heliocentric coverage by combining our P.I. data base (1 au heliocentric) with the spectral survey (3.2 - 3.6µm) acquired by the Hyakutake team at IRTF (0.45au). CO, C2H6, CH4, and methanol are present in both data sets, so we will begin with them. We expect to obtain rotational temperatures, production rates, and heliocentric dependence for detected species. Upper limits will be derived for interesting species when appropriate, and we will search for a possible signature of organic grains in the cometary continuum. The results will provide the first study of cometary organics based on a spectrally-complete, unbiased, high dispersion infrared spectrum of a bright comet.