Some meteorites probably come from comets. At present, none have been officially recognized, but scientists think they will soon identify some. A comet loses tons of ice when it passes close to the Sun. After about a thousand orbits, the comet's reserves of ice are exhausted. It is no longer active-only the solid nucleus continues its voyage around our star. At this point, the distinction between comets and asteroids becomes hazy. Meteorites from comets would have special characteristics because they formed a very great distance from the Sun. They would not be very dense and would have a high content of hydrated and carbonated minerals.