JAXA Spacecraft Data Indicate Massive Lava Tube on Moon

The SELENE (Kagiya) orbiter studied the moon using radar. (Credit: JAXA/SELENE/ Crescent/Akihiro Ikeshita)

Some very cool news out of Japan today where researchers say they have found an enormous lava tube stretching about 50 km (31 miles) under the lunar surface

The cavern, found in the Marius Hills area on the near side of the moon, is about 100 meters wide and extends for about 50 km, according to data taken by JAXA’s Selenological and Engineering Explorer (SELENE), also called the Kaguya moon probe.

In 2009, the Kaguya probe found a large shaft with an opening about 50 meters in diameter in the Marius Hills area. The shaft descends about 50 meters beneath the surface.

The JAXA team analyzed data obtained from a lunar radar sounder on the probe that indicated an underground structure extended west from the shaft.

The results were published in Geophysical Research Letters. You can find the abstract and a link to the paper here.

Location of lunar lava tube. (Credit: JAXA)

Information is not yet available on the English language version of JAXA’s website. However, the Japanese version of the website does have a story here that you can put through Google Translate.

  • windbourne

    That would be useful once nuclear reactors are up there to provide electricity and heat.

    Out of curiosity, anybody know if we have found lava tubes at either of the poles?
    That would be useful.

  • ThomasLMatula

    I suspect its likely ones will be found. But equally important are the large covered calderas that have been found, some 100’s of kilometers in area. Just add air, light and heat.

    Here is the paper on it.


    Paul D. Spudis, Patrick J. McGovern, Walter S. Kiefer
    Lunar Planetary Institute.

  • Tom Billings

    There are about 200 lava tube “candidates” on the Moon, from the Lunar Recon Orbiter data, listed by the Un. of AZ., almost always in the form of pictures of what look like “skylight” entrances. This is superior to the discovery method most often used on Earth for skylights, that often could be known as “the broken leg method”. The GRAIL experiment yielded data that was analyzed by a Purdue team, and the found indications of *many* more voids beneath the lunar surface.

    The Kaguya team seems to have spent the last 8 years grinding away to refine radar sounder data into a strong indication of the length and size of the Marius Hills hole. What is needed is an imaging ground-penetrating radar system in close orbit around the Moon with enough power to penetrate to depths of several kilometers, and a wavelength/aperture combination that can give us a resolution in the low meters range. IMHO, that is the best use for the lunar orbiting base currently proposed.

    The number of these candidates at the poles is unknown to me. What does interest me is the mention that the Marius Hills hole may have ice inside. Here on Earth, lava tubes get made into “Ice Caves” most often by having steep narrow entrances which winter air drops into, being heavier than air in the cave, …cooling the cave thereby. With the spring thaw, water from melting snow then dribbles into a cave well below freezing, and freezes to the rock walls and floor.

    On the Moon, the process would be longer term. A lunar cave entrance facing away from the equator and toward one of the poles would, over millions of years, possibly radiate away more heat during lunar night than sunlight can balance out during daytime. When comets strike the Moon, these caves would then be in the same situation as the areas at the lunar poles, freezing out the temporary gasseous atmosphere from the cometary impact. Perhaps the Kaguya team was able to get an indication of this, though the permittivity of ice being much closer to rock than that of water would make it a difficult thing to detect with a simple radar sounder system.

  • ThomasLMatula

    Yes, and if there is ice that means other frozen goodies may be present as well.

  • Paul451

    Not seeing how this 100m wide tube is “massive”, given that others are supposedly kilometres across.

  • publiusr

    Folks chide me on wanting domes. Fill one with air–can it hold a load it hasn’t “felt” before.

    Start with narrow ones.