This meteorite, called EETA 79001, was found on the ice in Antarctica, and is quite likely from Mars. For scale, the cube at the lower right is 1 centimeter on a side. The meteorite is partly covered by a black glassy layer, the fusion crust. The fusion crust forms when the meteorite enters the Earth's atmosphere at high speed. Friction heating melts the outer portion of the meteorite. Inside, the meteorite is gray. It is a basalt, very similar to basalts found on Earth. It formed in a volcanic eruption about 180 million years ago. This meteorite is quite likely from Mars because it contains a small amount of gas that is chemically identical to the Martian atmosphere.