Moon Sheds Light on Earth's Impact History

By looking at the Moon, the most complete and accessible chronicle of the asteroid collisions that carved our young solar system, a group of scientists is challenging our understanding of a part of Earth’s history. The number of asteroid impacts to the Moon and Earth increased by two to three times starting around 290 million years ago, researchers reported in a January 18 paper in the journal Science. They could tell by creating the first comprehensive timeline of large craters on the Moon formed in the last billion years by using images and thermal data collected by NASA’s Lunar Reconnaissance Orbiter (LRO). When the scientists compared those to the timeline of Earth’s craters, they found the two bodies had recorded the same history of asteroid bombardment—one that contradicts theories about Earth’s impact rate.