Future astronauts on the moon might need to hone their spelunking skills before they visit.
A new study from the SETI Institute and the Mars Institute looks at a series of pits seen by NASA's Lunar Reconnaissance Orbiter (LRO). These pits might actually be lava tube skylights, which are entrances to underground tunnels that were once filled with lava. Those tunnels could be key to accessing usable water on the moon.
The area of interest is the large Philolaus Crater near the moon's north pole. Planetary scientist Pascal Lee says the quality of the LRO images doesn't allow scientists to determine the pits are lava tube skylights with 100 percent certainty, but they are "good candidates considering simultaneously their size, shape, lighting conditions and geologic setting."
Researchers have already identified over 200 pits across the moon's surface that might be skylights, but the new study is the first to identify candidates located in the moon's polar region where water ice accumulates.
If there's ice inside the tubes, future expeditions might have much easier access to a usable water source than they would otherwise.
In a video on the research, Lee says water can be used for hydration, but can also be broken down into components needed for rocket fuel.
"Our next step should be further exploration, to verify whether these pits are truly lava tube skylights, and if they are, whether the lava tubes actually contain ice," Lee says.
The tubes could come into play as NASA considers potential landing sites for a future moon mission, whether with human astronauts or with robots.
They could also help prepare us to explore similar features on Mars some day. "There," Lee says, "we will face the prospect of expanding our search for life into the deeper underground of Mars where we might find environments that are warmer, wetter, and more sheltered than at the surface."