Orbit elements for the two Martian satellites Phobos and Deimos have been determined from 80 television photographs of the satellites taken by the imaging system of the Mariner 9 spacecraft. Phobos was found to be within 60 km of its positions predicted by recently published ephemeris theories which include a secular acceleration term in the longitude. This tends to corroborate the existence of a secular acceleration in the longitude of Phobos. Deimos was found to be within 100 km of its position predicted from earth-based observations. Comparison of the satellite's orbits determined from Mariner 9 data are made to these same ephemeric theories which are based on recent processing of earth-based observations. In addition, the magnitude of periodic perturbations to the satellite orbits due to Mars' gravity field and solar gravity are discussed and a 110 km long period perturbation in the longitude of Deimos is identified.
The motions of Phobos and Deimos from Mariner 9 TV data
1975-08-01
Miscellaneous
No indication
English
Viewing Phobos and Deimos for navigating Mariner
AIAA | 1972
|Viewing Phobos and Deimos for navigating Mariner 9.
NTRS | 1972
|Viewing Phobos and Deimos for Navigating Mariner 9
AIAA | 1974
|Mariner 9 television observations of Phobos and Deimos 2
NTRS | 1973
|AIAA | 1972
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