An International research team claims to have found a solar powered asteroid. The asteroid in question,1862 Apollo, is a relatively small heavenly body with a diameter of only 1.5 kilometers. It has a small moonlet, and its orbit crosses that of the Earth. The research team led by Academy Research Fellow Mikko Kaasalainen used brightness measurements from several years to reconstructed Apollo's shape and determine its rotational state. The team found that Apollo's rotation speed steadily increases as a result of re-radiation of solar energy from its surface. Kaasalainen said the study confirmed the theory that non-gravitional forces are important in the dynamical evolution of asteroids and that re-radiation of solar energy acts as a propulsion engine on the asteroid's surface.