A meteorite is a natural object of extraterrestrial origin that survives passage through Earth’s atmosphere and hits Earth’s surface. A meteorite is often confused with a meteoroid or a meteor. A meteoroid is a small object in outer space, generally less than 30 feet (10 meters) in diameter. A meteor (sometimes called a shooting star) is the flash of light seen when an object passes through Earth’s atmosphere and burns as a result of heating caused by friction. A meteoroid becomes a meteor when it enters Earth’s atmosphere; if any portion of a meteoroid lands on Earth, it is a meteorite.

There are three kinds of meteorites. Irons contain 85 percent to 95 percent iron; the rest of their mass is mostly nickel. Stony irons are relatively rare meteorites composed of about 50 percent iron and 50 percent silicates.