Earth may have once had a planetary ring

Cthe earth Did you once have a planetary ring like the one around Saturn? Scientists from Monash University in Australia think so. In recent research, they identified 450 million-year-old craters located near the Earth’s historic equator. They suggest that this was caused by the collapse of a ring of debris (perhaps the remains of a large asteroid) that was orbiting the planet. The ring probably lasted tens of millions of years, cooling the Earth with its shadow. ■