Citation

Abstract

Improvements in ground-based optical astrometry will eventually be required for navigation of interplanetary spacecraft when these spacecraft communicate at optical wavelengths. Although such spacecraft may be some years off, preliminary provements for the Galileo and Cassini missions. This article describes a technologydevelopment and observational program to accomplish this, including a cooperative effort with U.S. Naval Observatory Flagstaff Station. For Galileo, Earth-based astrometry of Jupiter’s Galilean satellites may improve their ephemeris accuracy by a factor of 3 to 6. This would reduce the requirement for onboard optical navigation pictures, so that more of the data transmission capability (currently limited by high-gain antenna deployment problems) can be used for science data. Also, observations of European Space Agency (ESA) Hipparcos stars with asteroid 243 Ida may provide significantly improved navigation accuracy for a planned August 1993 Galileo spacecraft encounter.

Details

Volume
42-110
Published
August 15, 1992
Pages
118–127
File Size
650.0 KB