Recent research reveals that a massive asteroid impact billions of years ago shaped two significant canyons on the moon’s far side. This discovery is promising for scientists and NASA, as they plan to land astronauts at the south pole on the Earth-facing side of the moon, an area that remains largely undisturbed and contains older, pristine rocks.
Using images and data from NASA’s Lunar Reconnaissance Orbiter, US and UK scientists mapped the site and determined that this event occurred approximately 3.8 billion years ago. The asteroid, estimated to be 25 kilometres wide, travelled past the lunar south pole before crashing, creating a vast basin and ejecting debris at nearly one kilometre per second, which formed the canyons within about ten minutes—far quicker than the millions of years needed for the Grand Canyon’s formation.
These findings were published in Nature Communications and highlight the geological violence of the event. Most debris was expelled away from the south pole, suggesting that the target exploration zone will remain largely free of disruption, allowing for the collection of ancient rocks that could provide insights into both lunar and Earth origins. Additionally, there’s interest in whether these canyons are in permanently shadowed areas, which may contain valuable resources such as ice, crucial for future lunar missions, including NASA’s Artemis programme aiming to return astronauts to the moon this decade.