How Sunlight Pushes Asteroids Rotating asteroids have a tough time sticking to their orbits. Their surfaces heat up during the day and cool down at night, giving off radiation that can act as a sort of mini-thruster. This force, called the Yarkovsky effect, can cause rotating asteroids to drift widely over time, making it hard for scientists to predict their long-term risk to Earth. Learn more here: http://1.usa.gov/1SgyCeT | NASA’s Goddard Space Flight Center