Cave discovered on the Moon raises hope for human colonization

Artists' rendering of SELENE (Kaguya) sounding lava tubes in orbit.  (Credit: JAXA/SELENE/Crescent/Akihiro Ikeshita for Kaguya image)

Space luminaries such as Elon Musk and Jeff Bezos have talked about building bases on the Moon to let humans live, work and play on the lunar surface.

A new discovery, however, may bring that dream to reality sooner than realized.

The Japan Aerospace Exploration Agency (JAXA) has discovered an enormous cave under the lunar surface, something it calls a “very significant” discovery, due to its value for both science and human expansion into space.

The discovery was made by Japan’s Selenological and Engineering Explorer (Selene) probe and shows a 50 kilometer (31 miles) “lava tube” underground, alongside a lava flow river “rille” on the Marius Hills of the Moon. JAXA used radio waves to confirm the existence of the cave after examining the hole.

Benefits of the cave

In a press release detailing the findings, JAXA outlined the reasons why the so-called lava tubes, which it believes were formed by volcanic activity on the Moon, are ideal for lunar bases. “Lava tubes may be the best place to build large-scale lunar bases because their interiors protect from dangerous space radiation, micrometeorite bombardment, and wide temperature oscillations,” the space agency wrote.

The underground area is approximately 310 miles long and 100 meters (328 feet) wide and may contain rocks filled with either water or ice. The cave has been given the nickname of Kaguya, a moon princess in a Japanese fairytale.

“We’ve known about these locations that were thought to be lava tubes … but their existence has not been confirmed until now,” Junichi Haruyama, a researcher at the Japan Aerospace Exploration Agency, told AFP on Thursday in comments obtained by The Guardian.

Haruyama, along with several others, is a co-author of the study.

A cave could shield humans from having to deal with the extreme temperatures on the Moon, due to its lack of atmosphere. During the day, temperatures can reach around 100 degrees Celsius (212 degrees Fahrenheit) and at night can reach as low as minus 173 degrees Celsius (minus 279.4 degrees Fahrenheit), according to

The volcanic activity, which is thought to have occurred between 3 and 4 billion years, gave the Moon a temporary atmosphere, however.

Space race is on

The study’s co-authors said that their work is just beginning as the search for lunar caves continues. They will look at other regions of the Moon for additional underground lava tubes for “future exploration of lava tubes or lunar base construction.”

Plans for human colonization of the Moon have heated up in recent months, with the likes of Musk and Bezos detailing plans for how their respective companies, SpaceX and Blue Origin will achieve the feat.

In May, Bezos said self-driving technologies, machine vision and other technologies could help rovers build a city on the Moon.

“There, you would want to pre-position a whole bunch of equipment and supplies before the humans show up, and some of those things might need to be assembled on the surface of the moon,” Bezos said in comments obtained by GeekWire. “And that’s the kind of thing that could also be done by advanced robotics with machine-learning systems on board.”

In September, SpaceX’s Musk outlined plans for a base on the Moon, codenamed Moon Base Alpha, utilizing the company’s BFR (Big F***ing Rocket) spacecraft.