Planetary scientists using data from NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission have discovered a 124-mile-wide crater on the nearside of the Moon, and provisionally named it after Amelia Earhart, the legendary aviator who disappeared 77 years ago while flying over the Pacific Ocean in a record attempt to fly around the world.
Bouguer gravity map of Earhart crater with overlay of topography. Image credit: Rohan Sood / Purdue University.
“Although some of this crater is visible at the surface of the moon, most of it is buried and could only be seen through gravity signatures captured during the GRAIL mission. This is one of the biggest craters on the moon, but no one knew it was there,” said team member Prof Jay Melosh of Purdue University.
“Craters are named after explorers or scientists, and Amelia Earhart had not yet received this honor. She attempted a flight around the world, and we thought she deserved to make it all the way to the moon for inspiring so many future explorers and astronauts.”
Prof Melosh and his colleagues from the Purdue University’s Earth, Atmospheric and Planetary Science and School of Aeronautics and Astronautics, were testing a new technique that sharpens the GRAIL data to see smaller-scale features, like ridges and valleys, when they noticed an unusual circular feature.
“The feature turned out to be the rim of an ancient crater, but it was so big we did not even recognize it as that at first,” said lead author Rohan Sood.
“We were zoomed in on one little piece of it. We first tried to model it as a small crater, but we had to go bigger and bigger and bigger to match what the data was telling us.”
The finding validates the team’s technique, and the group plans to extend the search to the entire Moon to reveal other buried craters and small-scale features beneath the lunar surface.
“The search could uncover underground tunnels formed by lava flows, called lava tubes, which have been discussed as a possible shelter for human habitats on the Moon,” Sood said.
The discovery was announced March 16 at the 46th Lunar and Planetary Science Conference in the Woodlands, TX.
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