[Previous] | [Session 17] | [Next]
N. Dello Russo (Catholic University/NASA-GSFC), M. J. Mumma (NASA-GSFC), M. A. DiSanti (Catholic University/NASA-GSFC), K. Magee-Sauer (Rowan University), R. Novak (Iona College), T. W. Rettig (Notre Dame University)
Ethane (C2H6) was detected in Comet C/1995 O1 Hale-Bopp on eleven dates between UT 1996 December 11.1 (Rh = 2.02 AU pre-perihelion) and UT 1997 August 8.8 (Rh = 2.24 AU post-perihelion) using the Cryogenic Echelle Spectrometer (CSHELL) at the NASA/IRTF. Long slit spectroscopy with CSHELL allowed the detection of ro-vibrational molecular lines in the infrared with high spectral (R ~ 20000) and spatial resolution. Comparison of spatial distributions for volatiles and dust can give insights into release mechanisms for observed coma molecules. The spatial distribution of ethane in the coma is consistent with its release directly from the nucleus on all dates measured. Preliminary production rates, rotational temperatures, and a heliocentric dependence for ethane production in Hale-Bopp based on a simple fluorescence model will be reported. The abundance of ethane relative to other volatiles will be compared for some recently observed comets. This work is supported by the NASA Planetary Atmospheres Program (NAG5-7753).