Janet Green, Space Hazards Applications, LLC; Paul O’Brien, The Aerospace Corporation; Rick Quinn, Atmospheric and Environmental Research; Stuart Huston, Space Hazards Applications, LLC; Paul Whelan, Space Hazards Applications, LLC; Nils Reker, Atmospheric and Environmental Research
Keywords: space weather, solar energetic particles, satellite anomalies, real time situational awareness
Abstract:
The number of satellites in Low Earth Orbit (LEO) or Medium Earth Orbit (MEO) is growing rapidly to support critical services such as internet and detailed imaging. At these altitudes, satellites may be protected from some space particle radiation but are still vulnerable to impacts from Solar Energetic Particles (SEPs). SEPs are a highly sporadic component of space radiation comprised of extremely energetic protons and heavy ions. They are produced in shock fronts that steepen ahead of Coronal Mass Ejections (CMEs) intermittently released from the sun. Once they reach Earth, these high energy ions can easily pass through outer satellite shielding and damage electronic components, resulting in temporary malfunctions, degraded performance, or a complete system or mission loss. Most satellites are designed to tolerate these relatively infrequent events but unexpected issues still occur especially during intense SEPs that may exceed design thresholds. Many of the new satellite mega-constellations may have unknown vulnerabilities because they were launched after the most recent large SEP event in 2017. The impacts to satellite operations from a large SEP may be further exacerbated because the events are likely to coincide with other intense space weather that changes atmospheric drag and creates tracking challenges. When an SEP occurs, it is necessary to define the regions of near-Earth space that will be most impacted. Some of the ions are deflected by Earths magnetic field creating partially shielded regions. Identifying which satellites are at risk for SEP related anomalies in LEO/MEO orbit is currently challenging because there are no easily available real time models and tools for defining where these energetic protons have access. In order to provide such monitoring information, we are developing the Solar Particle Access Model (SPAM). The model describes solar particle access at Earth by mapping real time measurements of high energy ions from low altitude satellites throughout the magnetosphere. It will be made available through an online application to easily deliver actionable information to users.
Date of Conference: September 14-17, 2021
Track: Atmospherics/Space Weather