22 of 90


142 million years ago, an asteroid or comet slammed into what is now the Missionary Plains in the Northern Territory, forming a crater 24 km (15 mi) in diameter. Due to erosion, the crater rim has been reduced to only 5 km (3 mi). Today, like a bull's eye, the circular ring of hills that defines Gosses Bluff (image center) stands as a stark reminder of the event shown in this high-resolution satellite photo. Image courtesy of USGS.