Airborne infrared spectroscopy of Comet Wilson (1986l) and comparisons with Comet Halley

Journal Article · Wed Mar 01 04:00:00 EST 1989 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/167260· OSTI ID:6062738

Larson, H P; Weaver, H A; Mumma, M J; Drapatz, S

H/sub 2/O and possibly CH/sub 4/ have been detected in near-infrared spectra of Comet Wilson (1986l). The observed number and relative intensities of cometary H/sub 2/O lines in the nu3 band at 2.65 microns were consistent with fluorescent excitation pumped by solar infrared photons. The H/sub 2/O production rate in Comet Wilson was approximately 3 x 10 to the 29th/s at R = 1.2 AU; no pronounced temporal variability was observed. Lines in the nu3 band of CH/sub 4/ at 3.3 microns were possibly detected at the 3 sigma confidence level. The CH/sub 4/ abundance is in the range CH/sub 4//H/sub 2/O = 0.014-0.045; the uncertainty is due primarily to the assumed effective excitation temperature of CH/sub 4/. The CH/sub 4/ abundance in this dynamically 'new' comet is similar to that observed in P/Halley. These values are low for equilibrium compositional models and very high for disequilibrium condensation in the solar nebula. 35 references.

• Research Organization: Arizona Univ., Tucson (USA); Arizona Univ., Tucson (USA); Space Telescope Science Institute, Baltimore, MD (USA); NASA, Goddard Space Flight Center, Greenbelt, MD (USA); Max-Planck-Institut fuer extraterrestrische Physik, Garching (Germany, F.R.)
• OSTI ID: 6062738
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 338; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640107* -- Astrophysics & Cosmology-- Planetary Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION SPECTRA
ABUNDANCE
ALKANES
CHEMICAL COMPOSITION
CHEMISTRY
COMETS
COMPARATIVE EVALUATIONS
COSMOCHEMISTRY
ELECTROMAGNETIC RADIATION
ENERGY-LEVEL TRANSITIONS
EXCITATION
HALLEY COMET
HYDROCARBONS
HYDROGEN COMPOUNDS
INFRARED RADIATION
INFRARED SPECTRA
METHANE
NEAR INFRARED RADIATION
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
RADIATIONS
SPECTRA
WATER