Meteors and shooting stars consist of very short-duration flashes in the sky, caused by a stone-like object flying into the earth's atmosphere from outside of it, and burning up. Occasionally, the object will reach the ground. Meteors have created many of the craters on the moon and similar ones here on earth. Until we went to the moon, meteorites (meteors which reach the earth) were the only extra-terrestrial material available here on earth.