The Astrometric Telescope Facility

The Astrometric Telescope Facility (ATF) proposed for use on NASA's planned Space Station is similar in form and data output to ground-based long focus astrometric instruments. With a focal plane scale of 12.7 arc seconds/mm, the strawman design has a field size of 10 arc min square and a limiting visual magnitude fainter than 16. Output from an observation includes the X and Y coordinates of each star and its relative brightness. The targeted precision for the AFT is 0.00001 arc seconds.