The preliminary result of orbital atmosphere detector on board spherical satellite

Abstract

<p indent="0mm">The spherical satellite is Chinese first spherical small satellite, integrating atmospheric composition, atmospheric density detection and precision orbit determination. The payload is the Orbital Atmosphere Detector, which was launched into near circular polar orbit with the orbit altitude of <sc>520 km</sc> and inclination angle of 97.4° on 14 October, 2021. The scientific objectives, operating principle and the ground calibration results of the Orbital Atmosphere Detector are presented in this paper. The preliminary <italic>in-situ</italic> observed results are analyzed and discussed. The observed mass densities are strongly correlated with <italic>F</italic>10.7 and <italic>Kp</italic>. The peak-to-valley ratio of observed mass densities during the quiet period of solar and geomagnetic activity on 3 November 2021 was 3.02; the peak of observed mass density increased from 2.8×10⁻¹³ to 8.0×<sc>10⁻¹³ kg/m³</sc> during the strong geomagnetic storm event on 4 November, 2021, an increase of 2.857 times compared to the MSIS00 model of 1.316 times. The observed data show that the increase in atmospheric density started at the South Pole and spread to the middle and low latitudes, while the MSIS00 model only show a weak symmetrically increase between the northern and southern hemispheres during the storm. The observed results show that the observed data objectively reflect the spatial and temporal distribution of thermosphere density during the quiet period and the geomagnetic storm event, and thermosphere atmospheric model correction can be implemented based on the large amount of observed data.