A substorm-dependent negative limit of non-eclipse surface charging of a
Chinese geosynchronous satellite
- Zhiyi Fu,
- Zhenpeng Su,
- Bin Miao,
- Zhiyong Wu,
- Yiren Li,
- Kai Liu,
- Xu Shan,
- Yuming Wang
Abstract
Surface charging is one of the most common causes of spacecraft
anomalies. When and to what potential the spacecraft is charged are two
important questions in space weather. Here, for a Chinese geosynchronous
navigation satellite, we infer the extreme negative surface charging
potentials from the ion differential fluxes measured by a low-energy ion
spectrometer. Without the solar eclipse effect away from the midnight,
the charging potentials are found to have a negative limit which is
determined by the maximum SuperMAG electrojet index in the preceding 2
hr. Such an empirical relation can be reasonably explained by the
dependence of 1--50 keV electron fluxes on substorm strength. Similar
relations may also exist for other inner magnetospheric spacecraft in
the non-eclipse region, which would be useful for spacecraft engineering
and space weather alerts.07 Nov 2023Submitted to ESS Open Archive 08 Nov 2023Published in ESS Open Archive