Relationship Between GOES-R Series Spacecraft Operational Anomalies and In Situ 30 eV–3-MeV Electron Measurements

The first two of NOAA’s Geostationary Operational Environmental Satellite (GOES)-R series spacecraft, GOES-16, and GOES-17, were launched in November 2016 and March 2018, respectively. Space weather instruments on board GOES-R Series spacecraft include the low- and high-energy magnetospheric particle sensors, MPS-LO and MPS-HI. These sensors measure 30-eV to ~3-MeV electrons in 25 differential energy channels and one integral (>2 MeV) channel. Since launch, a growing catalog of recurring GOES-R series operational anomalies has been maintained by the GOES-R program. A subset of the anomalies show a clear relation to ambient electron fluxes. These anomalies are primarily associated with the solar pointing platform (SPP) instruments and their interface with the spacecraft. The list of GOES-R operational anomalies and continuous in situ electron measurements from the same satellites provide an unsurpassed opportunity to study the interrelation between spacecraft errors and the ambient electron environment. In this work, we focus on one type of spacecraft anomaly involving telemetry between the extreme ultraviolet and X-ray irradiance sensors (EXIS) and the spacecraft. It is found that these anomalies occur more frequently when ambient electron flux levels are elevated. Comparisons with full distributions of measured fluxes and distributions of fluxes preceding anomalies show that the anomaly occurrences are most well associated with the elevation of ~130-keV electrons above normal levels, implicating shallow internal charging by electrons in the low hundreds of kiloelectron volts. This is confirmed by results from superposed epoch analysis (SEA) showing strong peaks in MPS-HI energy channels in the low hundreds of kiloelectron volts preceding the anomalies by ~30 min. Analysis of the local time dependence of the anomalies and measured fluxes reveal that there is a delay between the peak in ambient electron flux and anomaly occurrences suggesting a charging timescale of ~30 min to several hours.