Astronomers are able to study comets as they make their close approach to our sun. Their brilliant tails form as sunlight vaporizes their icy surfaces. But not all comets put on such a dazzling ...

Comets are leftovers, scraps of material that didn't make it to planethood in the events creating our solar system. Once, many astronomers believe, the solar system was full of comet nuclei ...

Europe's Rosetta mission officially ended Friday when the spacecraft purposefully crashed into its comet after spending two year orbiting the icy object in deep space. As the mission came to its ...