Global Ionizing Radiation Environment Mapping Using Starlink Satellite Data

We demonstrate the use of over 5000 commercial-off-the-shelf (COTS) complementary metal–oxide–semiconductor (CMOS) image sensors and simple total ionizing dose (TID) circuits from the Starlink satellite constellation to measure ionizing radiation effects in a low Earth orbit (LEO) environment with high spatial and temporal resolution. The constellation’s main operating environment was modeled, ground tests were performed on the CMOS image sensor (CIS) and TID circuit, and on-orbit data were collected and analyzed from nearly 3000 satellites in the primary 53° inclination shell. The estimated TID and bright spot counts are compared to model predictions and known LEO phenomena, respectively. The constellation of TID circuits provides high confidence in design margin against cumulative dose risk. Data on single-event effects (SEEs) in CIS are collected and shown to be capable of mapping high radiation regions of the orbit, such as the South Atlantic Anomaly (SAA). In total, this study demonstrates that thousands of low cost and readily available sensors hosted on mega-constellations can potentially inform future models by supplementing external data as a source of near real-time measurements of the radiation environment in LEO.