Atmospheric drag effects on the orbital decay and lifetime of a series of China satellite “SJ-2”

Abstract

A series of China Satellite “SJ-2” (1981-93A, 1981-93B, 1981-93D) was launched on 19 September 1981 by China 9 rocket (1981-93E). Due to the difference of the area-to-mass ratio, the atmospheric drag effects are different, therefore, the orbits decayed with different speeds. Their orbital lifetimes are 7 days, 382 days, 332 days, respectively. On the basis of the first-order theory of atmospheric drag perturbation, the orbits of 1981-93A and orbital drag perturbations caused by atmospheric effects were determined using a method of the corrected factor of the model of atmospheric density. The factors were determined by the observed orbital decay rate. In the paper we have analysed the atmospheric drag effects on the orbital decay and lifetime of SJ-2B (1981–93A) and compared the results from CIRA 1972 or CIRA 1986.