21652 Vasishtha is a main belt asteroid with an estimated diameter of 20 km. It was discovered on July 22 1999, by the Lincoln Laboratory Near-Earth Asteroid Research Team at Socorro. The semi-major axis is 2.27 AU, the eccentricity is 0.252 and the inclination is 11.98 degrees.
This asteroid was observed on five nights during August and September 21, 2003, using either 60 or 120 second exposures. A total of 587 images were used in the solution. Analysis of the data indicated a large amplitude and a period of 16.29 hours.