• Measuring positions, distances, and velocities of stars in known tidal streams would enable measurement of the Galactic potential to an accuracy of one percent.
  • Phase space discovery of new tidal streams, remnants, and substructure.
  • Accurate measurement of the distance to the Galactic Center
  • Measurement of the Galactic rotation curve
  • proper motions of M31, the Magellanic Clouds, and other Local Group Galaxies.
  • internal kinematics in the Magellanic Clouds and other Local Group galaxies.
  • kinematics and ages of young stars in star formation regions
  • measuring accurate distances for individual stars in star formation regions (Taurus-Auriga, Orion) too faint to be observed by Hipparcos.
  • calibrating the absolute luminosities of "standard candles" such as Cepheids and RR Lyrae stars.
  • Conservative detection thresholds predict approximately 9500 extrasolar giant planets in the OBSS catalog detected through astrometric wobbles out to 200 pc, of which 7500 would yield orbit solutions.
  • excellent temporal coverage would enable detection of 2000 giant planets through transit photometry
  • OBSS would detect more than 80 percent of near asteroids with a radius greater than 140 meter
  • would provide a warning efficiency above 90 percent for hazardous objects
  • would detect hundreds of new Kuiper Belt and trans-Neptunian objects

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