4.6 billion years ago, our solar system formed from a collection of gas and dust surrounding our nascent sun. While much of the gas and dust in this protoplanetary disk coalesced to form the planets, some of the debris was ...
Sep 10, 2015 in Space Exploration
What are asteroids made of? Asteroids are made mostly of rock—with some composed of clay and silicate—and different metals, mostly nickel and iron. But other materials have been found in asteroids, as well.
Sep 14, 2015 in Space Exploration