Asteroids are generally considered to be made up of metals and rocky material, while comets are made up of ice, dust and rocky material. ... Asteroids formed much closer to the sun, where it was too warm for ices to remain solid. Comets formed farther from the sun where ices would not melt. These are much larger than comets. An asteroid only 5 km across would be classi- fied as small; Ceres, the largest, is 100 times bigger than this.
Comet: A body of ice, rock and dust that can be several miles in diameter and orbits the sun. ... Meteor shower: A collection of meteors visible when Earth passes through a trail of debris left by a comet. Asteroid: An object larger than a meteoroid that orbits the sun and is made of rock or metal.
Each time a comet passes close to the sun, it loses more of its ice. Eventually, after many passes, the comet may no longer have enough material to form tails. Its surface will be covered by dark dust and it will look more like an asteroid.
comets are made up of ice, dust and rocky material. Asteroids are to be made up of metals and rocky material,