Lunar Cataclysm

Around four billion years ago, which would have been only shortly after it was formed, the Moon was pounded by a flurry of bodies in what scientists have dubbed the "lunar cataclysm." A new study, using data from the Lunar Reconnaissance Orbiter, finds that those cataclysmic flying rocks were not only numerous, they were also extremely energetic. Scientists interpret that increased energy as meaning the bodies were moving faster than normal.


So, why would they be moving faster during one specific period? Four billion years ago, the Solar System was still sorting itself out, settling into the system we know. Mighty Jupiter, especially, was disrupting the orbits of asteroids with its powerful gravitational field, throwing asteroids in towards the Sun. It was those asteroids that pummeled the Moon, creating some of the largest lunar basins we see today. As the giant planets established the orbits they have today, the bombardment of the inner System slowed to the occasional shot.