On Aug. 25, 2021, NASA's InSight lander, which touched down on the Red Planet in 2018, detected a powerful marsquake, designated S0976a. The Martian equivalent of an earthquake reached magnitude 4.2, which, at the time, was the most powerful quake that InSight or any other Mars lander had ever seen. (Since then, a 4.7 magnitude marsquake in May 2022 knocked it off the top spot, but S0976a remains second on this list.)