Jupiter - Structure and composition of the upper atmosphere
Abstract
The Voyager ultraviolet stellar occultation data yield a temperature of 200 + or - 50 K at about 400 km, and the solar occultation data give 1100 + or - 200 K at 1450 km above the ammonia cloud tops. The temperature gradient between 400 and 1450 km is approximately 1 K/km. The mesospheric temperature structure gives no strong indication of an earth-like mesopause. The heating of the upper atmosphere appears to result from a combination of magnetospheric charged particle precipitation, ion drag, inertia gravity waves, and solar EUV. The volume mixing ratios of CH4 and C2H6 at 325 km are measured to be 2.5(+3, -2) x 10 to the -5th and 2.5(+2.0, -1.5) x 10 to the -6th, respectively, which are lower than in the stratosphere. The C2H2 volume mixing ratio is not greater than 5 x 10 to the -6th at 300 km. The homopause value of the equatorial eddy diffusion coefficient is found to be 1-2 x 10 to the -6th sq cm/s.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 1981
- DOI:
- 10.1086/183586
- Bibcode:
- 1981ApJ...247L..43A
- Keywords:
-
- Atmospheric Composition;
- Atmospheric Heating;
- Atmospheric Temperature;
- Jupiter Atmosphere;
- Temperature Distribution;
- Turbulent Diffusion;
- Atmospheric Chemistry;
- Density Distribution;
- Exosphere;
- Mesosphere;
- Particle Precipitation;
- Plasma Heating;
- Stellar Occultation;
- Ultraviolet Spectrometers;
- Voyager Project;
- JUPITER;
- STRUCTURE;
- COMPOSITION;
- ATMOSPHERE;
- VOYAGER 1;
- TEMPERATURES;
- WAVELENGTHS;
- AMMONIA;
- CLOUDS;
- GRADIENTS;
- MESOSPHERE;
- IONS;
- DENSITY;
- HEATING;
- MAGNETOSPHERE;
- CHARGED PARTICLES;
- GRAVITY WAVES;
- EXPERIMENTS;
- RADIATION;
- MIXING;
- METHANE;
- ETHANE;
- STRATOSPHERE;
- EDDY DIFFUSION;
- ALTITUDE;
- PRESSURE;
- ULTRAVIOLET SPECTROMETER;
- ULTRAVIOLET;
- DATA;
- Lunar and Planetary Exploration; Jupiter