David A Galvan

Because of the widespread use of the Global Positioning System (GPS) for positioning, navigation, and timing (PNT), concerns have been expressed that a disruption of GPS might require a national investment in backup capabilities. The authors assess the costs associated with realistic threats to domestic, nonmilitary uses of GPS, and review possible additions to the PNT ecosystem in light of those costs.

Satellite anomalies are mission-degrading events that negatively affect on-orbit operational spacecraft. Maintaining a widely accessible and comprehensive database is one way to build an understanding of what situations are likely to result in satellite anomalies, but no such database exists. This report describes the nature and causes of satellite anomalies, and the potential benefits of a shared and centralized satellite anomaly database.