Ceres was once thought to be a member of an asteroid family. The asteroids of this family share similar proper orbital elements, which may indicate a common origin through an asteroid collision some time in the past. Ceres was later found to have spectral properties different from other members of the family, which is now called the Gefion family after the next-lowest-numbered family member, 1272 Gefion. Ceres appears to be merely an interloper in the Gefion family, coincidentally having similar orbital elements but not a common origin.