Somerville is an assumed
C-type asteroid.
Rotation period In March 2012, a rotational
lightcurve of
Somerville was obtained from photometric observations by American astronomer
Brian Warner at his Palmer Divide Observatory () in Colorado. Lightcurve analysis gave a
rotation period of 9.20 hours with a brightness amplitude of 0.80
magnitude ().
Diameter and albedo According to the surveys carried out by the Japanese
Akari satellite and the
NEOWISE mission of NASA's
Wide-field Infrared Survey Explorer,
Somerville measures between 24.90 and 33.60 kilometers in diameter and its surface has an
albedo between 0.017 and 0.04. The
Collaborative Asteroid Lightcurve Link derives an albedo of 0.0407 and a diameter of 22.84 kilometers based on an
absolute magnitude of 12.3. == Naming ==