Satellite Situation Center data system for magnetospheric science planning

Critical problems in planning coordinated observation campaigns for magnetospheric science include the need to predict time intervals when one or more observing satellites or ground stations will be connected along magnetic field lines to other observation sites, or when such sites will be located within magnetospheric regions of common interest. The Satellite Situation Center (SSC) was created at the National Space Science Data Center (NSSDC) during the International Magnetospheric Study in the 1970s to address these problems. The SSC Data System has evolved since that era to support potentially complex queries by SSC staff and has now been opened to NASA Science Internet access via the NSSDC On-line Data Information System (NODIS). The SSC software, ephemeris data base, and access modes are described for the Version 2.1 release in 1993.