Grand canyons on the Moon

Abstract

High energy streams of rock ejected from the Schrödinger impact basin carved two canyons in the lunar crust that are comparable in size to the Grand Canyon of North America. Here we use photogeologic mapping of those canyons and related impact ejecta deposits to show the trajectory of the impacting asteroid or comet, which produced an asymmetrical pattern of crater excavation and transport of ejected debris. The flow directions of that ejected debris and the speed of its subsequent impact with the lunar surface are calculated, as is the energy that carved the canyons in less than ten minutes. The study implies that most of the excavated debris was ejected away from the lunar south pole, minimizing the amount of debris that covers the > 4 billion year old units that will be explored by Artemis astronauts.