Ellen Phiddian
Cosmos science journalist
Astronomers say they’ve found a possible way to get into caves under the Moon’s surface on the Sea of Tranquillity.
The conduit they’ve discovered could be a cosy shelter for future crewed Moon expeditions.
The Italian and US researchers have published their findings in Nature Astronomy.
“These caves have been theorized for over 50 years, but it is the first time ever that we have demonstrated their existence,” says senior author Professor Lorenzo Bruzzone, an astronomer at the University of Trento, Italy.
The Moon’s surface is dotted with pits, sometimes called skylights, which have been formed by lava tubes caving in.
“Although more than 200 pits have now been detected in various lunar geological settings and latitudes, it remains uncertain whether any of these openings could lead to extended cave conduits underground,” write the researchers in their paper.
The team used 2010 radar data from NASA’s Lunar Reconnaissance Orbiter to examine the Mare Tranquillitatus, or Sea of Tranquillity, pit.
“The Miniature Radio-Frequency instrument acquired data that included a pit in Mare Tranquillitatis,” says Bruzzone.
“Years later we have reanalysed these data with complex signal processing techniques we have recently developed, and have discovered radar reflections from the area of the pit that are best explained by an underground cave conduit.”
The conduit, the researchers believe, is between 30-80 metres long, about 45m wide, and about 130-170m below the Moon’s surface.
“This discovery provides the first direct evidence of an accessible lava tube under the surface of the Moon,” says Bruzzone.
Such a tube would be shielded from the radiation and temperature extremes that occur on the surface of the Moon which makes it a promising site for any potential lunar bases.
“This research demonstrates both how radar data of the Moon can be used in novel ways to address fundamental questions for science and exploration and how crucial it is to continue collecting remotely sensed data of the Moon,” says co-author Dr Wes Patterson, from the Johns Hopkins Applied Physic Laboratory, US.
