Joint Milli-Arcsecond Pathfinder Survey (J-MAPS) Mission: The Application of High Metric Accuracy Astrometry to Space Situational Awareness

摘要

Two critical aspects of the Space Situational Awareness (SSA) problem are detection and orbit generation for Resident Space Objects (RSOs). The two problems have two different instrumentation solutions. Existing and planned ground and space-based optical systems are optimized for detection, with the result that their ability to measure the position and velocity of RSOs of interest is compromised. An SSA architecture would potentially benefit from supplementing existing and planned detection assets with a dedicated high- accuracy orbit determination system or systems, with the potential for 24/7 taskability and near-real time capability. By optimizing an instrument to perform position measurement rather than detection, significant (i.e., one or more orders of magnitude) improvement may be realized in position and velocity measurement (thus, orbit determination) vs. other current and envisioned systems. The United States Naval Observatory (USNO) is developing the space- based J-MAPS mission to support current and future star catalog and star tracker requirements. By its very nature, USNO's J-MAPS mission, a microsatellite designed to take very high precision measurements of star positions (astrometry), is ideally suited to make these high metric accuracy measurements for brighter GEO RSOs. Background material is presented on the current state of astrometric measurements from ground and space, and we will motivate the need to apply high metric accuracy astrometry to the SSA problem. As a solution, we will discuss capabilities of the J-MAPS mission. To support SSA, J-MAPS would demonstrate the ability to measure geosynchronous satellite positions to absolute accuracies of better than 10 m (plane-of-the-sky), the ability to autonomously range with accuracies of order 100 meters over a few tens of minutes of observing time, and the ability to monitor regions around specific assets and detect and observe delta-V maneuvers.