Andesite, a fine-grained rock that is widely distributed in the earth's crust. Andesite reaches the surface as lava from volcanoes. As it cools it forms gray to grayish-black sheets, often in thick accumulations. Andesite consists chiefly of feldspar minerals mixed with smaller amounts of iron and magnesium. It was named for the Andes of South America, where it is widely found. Andesite is used for building stone and monuments.
When a star dies, it becomes a black hole. Once something passes through the it's gone for good, never to be seen or heard from again. If we lived next to a black hole, would it suck us in too?
Every November, the Leonid meteor shower fills the sky with "shooting stars." This year, the shower is expected to peak twice. Learn how Leonid and other meteor showers work.