  The Joint Milli-Arcsecond Pathfinder Survey (JMAPS) mission is a Department
of Navy (DoN) space-based, all-sky astrometric bright star survey. JMAPS is
currently funded for flight, with at 2012 launch date. JMAPS will produce an
all-sky astrometric, photometric and spectroscopic catalog covering the
magnitude range of 1-12, with extended results through 15th magnitude at an
accuracy of 1 milliarcsecond (mas) positional accuracy at a mean observing
epoch of approximately 2013. Using Hipparcos and Tycho positional data from
1991, proper motions with accuracies of 100 microarcseconds (umas) per year
should be achievable for all of the brightest stars, with the result that the
catalog will degrade at a much reduced rate over time when compared with the
Hipparcos catalog. JMAPS will accomplish this with a relatively modest
aperture, very high accuracy astrometric telescope flown in low earth orbit
(LEO) aboard a microsat. Mission baseline is for a three-year mission life
(2012-2015) in a 900 km sun synchronous terminator orbit.
