Space Caves: Italian scientists have presented evidence of underground caves on Earth's natural satellite. Researchers and space companies are already enthusiastic about the future scientific and business prospects of a large-scale colonization of the Moon.

A new study published in Nature proposes the first true evidence of an "accessible cave conduit" on the Moon, located beneath the Mare Tranquillitatis pit. A future human mission could exploit this or other underground caves to build one or more permanent lunar outposts, potentially opening a whole new chapter in space exploration on the Moon and beyond.

A team led by Leonardo Carrer, an assistant professor at the University of Trento, confirmed a long-debated theory about the Moon. Natural, stable structures created by ancient lava tubes have been theorized for decades, and the Italian researchers have now discovered the first signs of one of these underground structures thanks to data collected by the Lunar Reconnaissance Orbiter (LRO) in 2010.

By studying variations in radar reflections and creating 3D simulations based on the LRO's database, the researchers discovered a natural phenomenon that could be explained by the lava tube theory. The Moon's surface hosts more than 200 known "pits" in different regions, and the Mare Tranquillitatis pit is the deepest one known so far.

The Moon has no atmosphere, which means that a human exploration mission would face numerous challenges from extreme temperature variations, the Sun's electromagnetic radiation, meteorites, and the regolith deposits making up the outermost layer of the surface. However, a few hundred meters below the surface, temperatures would remain steady at around 17 degrees Celsius, and there would be no impeding dangers to human explorers coming from outer space. Just to be clear, there would still be no air to breathe.

Researchers are now proposing a complete survey of all known lunar pits using the same methodology as in the recently published study. This way, we could identify the most promising access points for future subsurface lunar exploration or even collect information useful for building and installing a human base in a comfortable, underground (and protected) environment.

NASA is currently trying to build momentum for its Artemis program, which aims to open a new era for Moon and outer space exploration. The program's long-term goal is to establish a permanent human base on the Moon, thus facilitating future missions to Mars. Ancient underground caves could very well turn the lofty goal of the US space agency into a very real prospect, with unprecedented possibilities for space exploration and the lunar economy.