NASA’s astronauts have walked the lunar surface during the Apollo missions and will likely do it again in just a few years for the Artemis program. Now, new evidence appears to confirm visitors may one day explore the moon’s interior—and even live or work within them. According to findings published July 15 in Nature Astronomy, an international team of researchers led by professors at Italy’s University of Trento believe they have finally demonstrated the presence of tunnels within the lunar subsurface.
Astronomers have theorized about lunar cave networks for over 50 years, but their existence has long been a subject of debate. In 2009, researchers discovered a deep hole in the moon that supported the hypothesis that tunnels may form when lava cools underneath the surface. Monday’s news, however, is reportedly first of its kind to seemingly demonstrate the existence of lengthier conduits.
[Related: We could live in caves on the moon. What would that be like?]
Using recent advancements in signal processing analysis, experts reviewed scans of a pit located in the moon’s Mare Tranquillitatis region taken in 2010 by the Miniature Radio-Frequency (Mini-RF) instrument aboard NASA’s Lunar Reconnaissance Orbiter. Based on observations of these radar reflections, the team is confident they discovered an opening accessible to astronauts.
“Thanks to the analysis of the data we were able to create a model of a portion of the conduit,” Leonardo Carrer, a researcher at University of Trento, says in an accompanying statement. “The most likely explanation for our observations is an empty lava tube.”
According to an additional statement from Wes Patterson, the Mini-RF principal investigator at the Johns Hopkins Applied Physics Laboratory, their paper shows how radar data can be utilized in new and creative ways, as well as how “crucial it is to continue collecting remotely sensed data of the moon.”
While initial plans for a permanent human lunar presence center on establishing an above ground base of operations, their long term health may rely on moving into tunnel systems like the one within Mare Tranquillitatis. As Japan’s SLIM lunar lander recently reminded the world, the moon is an extremely harsh environment, even for machines. Temperatures during a lunar day can reach 260 degrees Fahrenheit, while two-week long lunar nights plummet to nearly -280 degrees Fahrenheit. Meanwhile, solar and cosmic radiation bombardments are as much as 150 times more intense than what humans experience on Earth. Throw in the ever-present possibility of meteorite impacts, and burrowing into these lava tunnels could provide much needed safety for anyone looking for an extended stay on (or in) the moon.
Although temperatures wouldn’t be more pleasant in these conduits, they could easily shield visitors from all that radiation and space debris. There’s also the possibility of using such networks to mine for valuable lunar resources like metals and even possible ice reserves. Doing so would dramatically reduce the cost and logistics required to otherwise transport materials from Earth.