Half-baked Asteroids Have Earth-Like Crust

The article, "Half-baked Asteroids Have Earth-Like Crust", helps to tell us about the history of our solar system by talking about two meteorites found in Antarctica. These two meteorites have a crust that is unusual to that of most other meteorites found on Earth because the rock that makes up the crust is an igneous rock known as andesite. Andesite is very common on Earth where volcanic eruptions formed the crust made out of this rock.  The age of these meteorites is thought to be around 4.5 billion years old, which would mean that they formed around the time that our solar system was born. Because they are very old, as the article says, it is unlikely that they broke off from another planet. Scientists believe that the asteroid these meteorites come from is about 100 kilometers in diameter, which is large enough to hold heat to partially melt the asteroid's rocks. These melted portions of the rock would erupt up, and form the andesitic crust. After reading this article, I thought it was amazing that scientists are able to find out so much about our solar system and this asteroid from the small meteorite samples that landed on earth.

http://www.sciencedaily.com/releases/2009/01/090107134526.htm