Accession Number : AD0669995

Title :   ROLL RESONANCE FOR A GRAVITY-GRADIENT SATELLITE.

Descriptive Note : Technical memo.,

Corporate Author : JOHNS HOPKINS UNIV SILVER SPRING MD APPLIED PHYSICS LAB

Personal Author(s) : Whisnant,J. M. ; Anand,D. K.

Report Date : APR 1968

Pagination or Media Count : 19

Abstract : Previous studies of gravity-gradient satellite attitude stabilization showed that large roll angles could occur for a partially shadowed orbit. The cause was determined to be a resonance effect due to solar radiation pressure. An expression for the solar torque for roll on a dumbbell-shaped satellite is presented herein. The amplitude of the torque is shown to be a function of the angle between the satellite-sun line and the normal to the orbit plane. For circular orbits, an expression is derived to determine for what position of the sun relative to the orbit plane the resonance effect is a maximum. For orbits of modest eccentricity, the amount of orbit shadowed as a function of sum-orbit orientation is determined. The persistance of the resonance effect for retrograde orbits is discussed. (Author)

Descriptors :   (*SATELLITE ATTITUDE, ROLL), STABILIZATION, RESONANCE, SOLAR RADIATION, PRESSURE, MATHEMATICAL ANALYSIS, CIRCULAR ORBITS, ELLIPTICAL ORBIT TRAJECTORIES, SCIENTIFIC SATELLITES

Subject Categories : Numerical Mathematics
      Astronautics
      Unmanned Spacecraft
      Spacecraft Trajectories and Reentry

Distribution Statement : APPROVED FOR PUBLIC RELEASE