I f astronomers had been walking the Earth 466 million years ago, they may have had something special to see. The moon and the planets and the stars and the sun would have looked

Evidence suggests Earth had a ring system 466 million years ago, causing a surge in meteorite impacts and possibly influencing the planet's climate.

A ring could explain a mysterious arrangement of impact craters near the equator and might even have caused an ice age, according to a new study