This artist's concept shows a possible explosion resulting from a high-speed collision between a space rock and Jupiter's moon Europa. Clay-type minerals have been found on Europa's surface in a new analysis of data from NASA's Galileo mission. The pattern of these minerals suggests an asteroid about 3,600 feet (1,100 meters) across or a comet about 5,600 feet (1,700 meters) across could have hit at a shallow angle. Clay-type minerals are commonly found in primitive asteroids and some comets. These kinds of asteroids and comets also typically carry organic compounds, providing a possible way for organics to be delivered to Europa.