SIM Lite measurements of Milky Way stars were to yield data to understand four topics: fundamental galactic parameters, the Oort Limit, disk mass potential, and mass of the Galaxy to large radii. The first, fundamental galactic parameters, was aimed at answering key questions about the size, shape and the rotation rate of the Milky Way. The team hoped to more accurately determine the distance from the Sun to the galactic center. The second topic, the Oort Limit, would have attempted to determine the mass of the galactic disk.