Small meteorites are slowed by our atmosphere and, when they land, often make shallow indentations in the ground known as impact pits. Larger meteorites may form craters, while the most massive space rocks produce gigantic impact features called astroblemes, or “star wounds.” The biggest astroblemes on Earth are millions of years old and more than one hundred miles across, making them greater in area than some countries. Those meteorite impacts generated atomic bomb-sized levels of heat and pressure that melted Earth rocks into unique materials known as impactites. Most times, meteorites that made those giant craters have long since weathered away, but the ghostly footprints of their cataclysmic collisions with Earth remain with us to this day —as impactites.
