Accession Number : AD0759806

Title :   Navigation Schemes for LES-8/9 Autonomous Stationkeeping System.

Descriptive Note : Technical note,

Corporate Author : MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB

Personal Author(s) : Srivastava,Sushanta

Report Date : 20 APR 1973

Pagination or Media Count : 27

Abstract : TEM.Technical note,Srivastava,Sushanta ;TN -1973-18F19628-73-C-0002AF-649LESDTR-73-85(*synchronous satellites, *celestial guidance), (*scientific satellites, *circular orbits), detectors, horizon scanners, yaw, drift, attitude control systems, celestial mechanicsles-9 satellite, les-8 satellite, stationkeeping, design specificationsThe autonomous stationkeeping system for LES-8/9 controls the mean longitude of the satellite by on board navigation. The longitude is computed from the observations of an infrared earth-horizon scanner, sun azimuth transit sensors and an earth-shadow sensor. The compensation for non-uniform sun motion for any near ecliptic satellite orbit is generated by an ephemeris synthesizer. The time reference is obtained from a stabilized oscillator. The report describes various considerations for the design of the navigation scheme. (Author)

Descriptors :   (*SYNCHRONOUS SATELLITES, *CELESTIAL GUIDANCE), (*SCIENTIFIC SATELLITES, *CIRCULAR ORBITS), DETECTORS, HORIZON SCANNERS, YAW, DRIFT, ATTITUDE CONTROL SYSTEMS, CELESTIAL MECHANICS

Subject Categories : Space Navigation and Guidance
      Unmanned Spacecraft
      Spacecraft Trajectories and Reentry

Distribution Statement : APPROVED FOR PUBLIC RELEASE