| タイトル | Viking Radio Occultation Measurements of the Martian Atmosphere and Topography: Primary Mission Coverage |
| 著者（英） | Grossi, M.; Michael, W., Jr.; Fjeldbo, G.; Brenkle, J.; Seidel, B.; Christensen, E.; Mehta, J.; Farless, D.; Wallio, A.; Sweetnam, D. |
| 著者所属（英） | Jet Propulsion Lab., California Inst. of Tech.; NASA Langley Research Center; Raytheon Co. |
| 発行日 | 1977-09-30 |
| 言語 | eng |
| 内容記述 | Radio occultation measurements were made at approximately 50 locations on Mars with the Viking Orbiter 1 S (2.3 GHz) and X (8.4 GHz) band tracking links during October 1976. The measurements have been used to study the topography and atmosphere of Mars at latitudes ranging from about 75 deg S to 70 deg N. By using the ingress and egress times obtained from the observed limb diffraction effects together with the best ephemerides available for the orbiter and the planet we have determined the surface elevations at the occultation points relative to the reference areoid. The observations agree with Mariner 9 and radar data to within 2 km. The mean atmospheric pressure at the areoid level was found to be 5.9 mbar during the northern midsummer season, a value which agrees quite well with data obtained at the landing sites. By comparing the new electron density measurements with earlier Mariner data we have determined that the temperature and the plasma scale height of the upper atmosphere appear to be functions of solar activity. |
| NASA分類 | LUNAR AND PLANETARY EXPLORATION |
| レポートNO | 78A11422 |
| 権利 | Copyright |
|
