Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published July 1, 1980 | Published
Journal Article Open

Hydrocarbon photochemistry and Lyman alpha albedo of Jupiter

Abstract

A combined study of hydrocarbon and atomic hydrogen photochemistry is made to calculate self-consistently the Lɑ albedo of Jupiter. It is shown that the Lɑ emissions observed by Voyagers I and II can be explained by resonance scattering of sunlight. Precipitation-of energetic particles from the magnetosphere can provide the large required source of atomic hydrogen, although the contribution of direct particle excitation to the disk-averaged brightness is insignificant. The variability of the Lɑ brightness inferred from many observations in recent years is examined. The large difference in the brightness of the He 584 Å resonance line observed by Pioneer and Voyager is briefly discussed. Driving the photochemistry by solar ultraviolet radiation alone yields a maximum mixing ratio of C_2H_6 + C_2H_2 at 10^(-2) atm of about 4 x 10^(-6). The possibility of additional CH_4 dissociation from precipitation of magnetospheric particles is discussed. The photochemistry of C_2H_2 and C_2H_3 is sufficiently uncertain not to permit accurate calculations of their densities and the ratio C_2H_6/C_2H_2.

Additional Information

© 1980 American Astronomical Society. Provided by the NASA Astrophysics Data System. Received 1979 December 6; accepted 1980 January 8. We thank A. L. Broadfoot and his team for providing us with preliminary data, G. R. Gladstone, and W. Huntress for helpful discussion. We thank the referee D. M. Hunten for improving our paper in many ways. This research was supported by NASA contract NSG-7376 to the California Institute of Technology under the Planetary Atmosphere Program.

Attached Files

Published - 1980ApJ___239__395Y.pdf

Files

1980ApJ___239__395Y.pdf
Files (963.9 kB)
Name Size Download all
md5:2dc7891aa83227dd881de524f72195fe
963.9 kB Preview Download

Additional details

Created:
August 22, 2023
Modified:
October 17, 2023