A team of researchers with Purdue University has found evidence from lunar-mapping spacecraft that the moon may have large lava tubes that could conceivably be used to house astronauts and supplies. In their paper published in the journal Icarus, the team describes their study of data from NASA’s Gravity Recovery and Interior Laboratory (GRAIL) twin spacecraft and outline the evidence for large lava tubes.
Prior research here on Earth has shown that lava flowing across a surface can form a shell of sorts as it cools, and when the shell collapses, a hollowed-out underground space remains—geologists call them lava tubes. Examples have been found in Hawaii and Iceland. Now, the researchers at Purdue believe they have found evidence that such structures might exist just below the surface of the moon in some places as well.
The evidence from GRAIL consists of very small variations in the moon’s gravitational pull, suggesting differences in density below the surface. There is also some evidence of skylights in photographs taken of the moon near the areas of the gravitational variations. Skylights are areas on the surface that occur when part of a lava tube collapses creating a window of sorts into the tube below. The team built a geology-based computer model using the data they had gathered from GRAIL and the photographs, along with other known information about lava tubes here on Earth and other features unique to the moon. The model then offered predictions regarding the possible existence of lava tubes below the surface of the moon and how big and stable they might be—the researchers reasoned that they could be much larger than those found on Earth due to less pressure from gravity.
The model indicated that lava tubes were likely present and that they could be as wide as three miles across and still remain stable. Such a wide, long tube, the researchers note, might be an ideal form of shelter for future astronauts—they could live in the tubes along with all their gear free from the fear of being struck by space debris and the constant barrage of solar radiation. It would likely be easier to manage temperature control as well, making life less dangerous for future moon residents.
Filed Under: Aerospace + defense