A weird number of craters are located close to the equator, and the odds that this is random are incredibly low, researchers say.

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

C ould Earth once have had a planetary ring like the ones around Saturn? Scientists from Monash University in Australia think so. In a recent paper they identify 450m-year-old craters that lie close to Earth’s historical equator.