Moon’s Lava Tubes May Allow for Underground Cities

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“There has been some discussion of whether lava tubes might exist on the moon,” announced Jay Melosh, a Purdue University distinguished professor of Earth Atmospheric and planetary sciences in a Purdue press statement released March 19, according to

“Some evidence, like the sinuous rilles observed on the surface, suggest that if lunar lava tubes exist they might be really big,”added Melosh.

New theoretical work suggests that these features could be large enough to house structurally stable lunar cities for future colonists. Data from NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission suggests that lava tubes on the moon could have diameters in excess of more than half a mile (1 kilometer), reported .

These features could support future long-term human exploration on the moon, offering shelter from cosmic radiation, meteorite impacts and the wild temperature swings of lunar day and night, explains

The edges of the lava cool as it flows to form a pipe-like crust around the flowing river of lava. When the eruption ends and the lava flow stops, the pipe drains leave behind a hollow tunnel, stated  Melosh. The Purdue team found that if lunar lava tubes existed with a strong arched shape like those on Earth, they would be stable at sizes up to 5,000 meters, or several miles wide, on the moon.

“This wouldn’t be possible on Earth, but gravity is much lower on the moon and lunar rock doesn’t have towithstand the same weathering and erosion,” stated David Blair, a graduate student in Purdue’s Department of Earth, Atmospheric and Planetary Sciences who led the study that examined whether empty lava tubes more than 1 kilometer wide could remain structurally stable on the moon, reported

“In theory, huge lava tubes big enough to easily house a city could be structurally sound on the moon,” added Blair.