气球卫星1990—81B和1990－81C的轨道变化和高层大气密度的测定

本文测定给出我国首次发射的专用于高层大气探测的两颗气球卫星ＤＱ－１Ａ（１９９０－８１Ｂ）和ＤＱ－１Ｂ（１９９０－８１Ｃ）整个寿命期间的轨道变化，以及利用轨道衰变率，采用适合气球卫星近国轨道反测密度的一种方法，获得５００—９００ｋｍ高度范围内太阳峰年期间的高层大气密度及其变化．结果表明，同时发射的两颗面积质量比不同的气球卫星所测定的高层大气密度及其变化非常一致，且明显地显示密度随太阳活动逐日的和２７天周期性的变化．本文将密度测定结果与高层大气模型进行了比较和分析．

THE ORBITAL VARIATIONS OF BALLOON SATELLITES 1990-81B AND 1990-81C AND DETERMINATION OF AIR DENSITY

The orbital variations of two balloon satellites, DQ-1A(1990-81B)and DQ-1C(1990-81C), are determined and presented in this paper. A practical method for determining air density from the decay rate of nearly circular orbit is used and the upper atmospheric densities and variations at heights of 500-900km during the period when solar activity was just at a high level have been obtained from two balloon satellites. The results show that two sets of the density and variations determined respectively from two balloon satellites with different area/mess ratios are good agreement with each other and the variations of density with daily and 27 days periodically time scales of solar activity are very obvious. A comparison between observed density and the COSPAR International Reference Atmosphere 1972 and 1986 is made in this paper. The analytic results are valuable for the study of space environments and the application of upper atmosphere model.