Submillimeter Observations of Planets
Abstract
A new program of ground-based observations at submillimeter (≈400 μm) wavelengths has yielded observations of Mercury, Venus, Mars, Jupiter, and Saturn. We report here observations near planetary conjunctions, which have minimal corrections for atmospheric extinction: Mercury, 361±65 K; Venus, 231±35 K; and Saturn, 205±15 K (based upon the area of the planetary disk), using Jupiter (150 K) and Mars (220 K) as photometric standards. The Mercury observations show that the brightness temperature does not decrease at the submillimeter wavelengths, relative to observations at 3 mm; for Venus, however, the brightness temperature appears appreciably lower than at millimeter wavelengths. The results for Saturn indicate a strong and possibly optically thick contribution from the rings. We also gave a description of our instrumentation and observational techniques, with special emphasis upon the effect of extinction by atmospheric water vapor.
- Publication:
-
Icarus
- Pub Date:
- November 1974
- DOI:
- 10.1016/0019-1035(74)90055-4
- Bibcode:
- 1974Icar...23..374H
- Keywords:
-
- Astronomical Photometry;
- Infrared Astronomy;
- Planetary Atmospheres;
- Planetary Surfaces;
- Submillimeter Waves;
- Brightness Temperature;
- Jupiter (Planet);
- Mars (Planet);
- Mercury (Planet);
- Radio Astronomy;
- Saturn (Planet);
- Venus (Planet)