Jovian aurora: electron or ion precipitation

Technical Report · Wed Jan 01 00:00:00 EST 1986

OSTI ID:6740627

Waite, Jr, J H; Clarke, J T; Cravens, T E

High signal-to-noise spectra of the Jovian aurora at UV wavelengths obtained using the International Ultraviolet Explorer Observatory (including the brightest Jovian aurora observed to date) set strigent upper limits for sulfur and oxygen emissions, which would be associated with the precipitation of energetic heavy ions in the upper Jovian atmosphere if they were solely responsible for Jovian auroral processes. Model calculations of heavy ion precipitation and corresponding estimates of the associated sulfur and oxygen UV emissions previously carried out suggest emission values for 1304 A OI emission that are at least 30 times larger than the upper limit values set by the IUE observations reported. On the other hand the observed (feature of SII at 1256 A of 2 kR) is quite comparable to the theoretically predicted emission intensity. Taken together these observations and calculations suggest that electron as well as ion precipitation play a role in Jovian auroral processes. In light of earlier X-ray observations and in-situ plasma observations that suggest energetic heavy ion precipitation in the Jovian auroral zone, a scenario is suggested where heavy ion auroral energy deposition is concentrated at altitudes below the homopause. Electrons with energies of 10 to 30 keV are responsible for the bulk of the observable UV and EUV emissions since they deposit their energy above the methane absorbing layer defined by the homopause.

• Research Organization: National Aeronautics and Space Administration, Huntsville, AL (USA). George C. Marshall Space Flight Center
• OSTI ID: 6740627
• Report Number(s): N-88-24566; NASA-TM-101153; NAS-1.15:101153
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
JUPITER PLANET
AURORAE
CHARGED-PARTICLE PRECIPITATION
ULTRAVIOLET SPECTRA
PLANETARY ATMOSPHERES
ELECTRON PRECIPITATION
HEAVY IONS
MATHEMATICAL MODELS
THEORETICAL DATA
ATMOSPHERES
CHARGED PARTICLES
DATA
INFORMATION
IONS
NUMERICAL DATA
PLANETS
SPECTRA
640107* - Astrophysics & Cosmology- Planetary Phenomena