15.17-P

Abundances of C tex2html_wrap_inline21 H tex2html_wrap_inline23 (Ethylene) and Other Small Molecules in Neptune's Atmosphere from Voyager 2 Infrared Observations

W. C. Maguire (NASA/GSFC)

Infrared spectra measured between 2 days before to 2 days after Voyager 2's August 1989 encounter were averaged. These 2351 spectra ranged from tex2html_wrap_inline25 N to tex2html_wrap_inline27 S. In this average, we have previously identified the Q-branch of tex2html_wrap_inline29 C tex2html_wrap_inline21 H tex2html_wrap_inline23 (ethylene) at 950 cm tex2html_wrap_inline35 . From a recent measurement of ethylene's tex2html_wrap_inline29 band strength, we have redetermined a mole fraction 3.5 tex2html_wrap_inline39 tex2html_wrap_inline41 10 tex2html_wrap_inline43 for ethylene in Neptune's atmosphere. Abundances of other gaseous atmospheric molecules containing small numbers of atoms will also be presented.