EUVE Observations of Jupiter During the Impact of Comet Shoemaker-Levy 9
G. Randall Gladstone 1,
Doyle T. Hall 2, and
J. Hunter Waite Jr. 1
1 Department of Space Sciences, Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78228, USA.
2 Center for Astrophysical Sciences, Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA.
The Extreme Ultraviolet Explorer (EUVE) satellite conducted extensive observations of the jovian system before, during, and after the impact of the fragments of comet Shoemaker-Levy 9 in July 1994. About 2 to 4 hours after the impacts of several of the larger fragments, the brightness of the neutral helium (He I) resonance line at 58.4 nanometers temporarily increased by a factor of about 10. The transient 58.4-nanometer brightenings are most simply explained by resonant scattering of sunlight from the widespread high-altitude remnants of the larger impact plumes. Other possible sources of emission, such as electron impact excitation of He or radiative recombination of He+, may contribute to the observed signal.
Submitted on October 18, 1994
Accepted on March 15, 1995