The mission, known as GIMLI, will directly study the Marius Hills Pit, a feature located on the Moon’s near side in an ancient volcanic region. The project is being developed under NASA’s Payloads and Research Investigations on the Surface of the Moon programme and is led by the Planetary Science Institute (PSI).
The Marius Hills Pit is about 34 metres deep and measures roughly 65 by 90 metres across. While satellite images have confirmed the pit’s existence, scientists have yet to determine whether it connects to a larger underground cavity.
GIMLI, short for Geophysical Investigation of the Marius Hills Pit Lava Tube and Interior, will use several scientific instruments to investigate the structure beneath the lunar surface.
The mission is expected to use ground-penetrating radar, seismic sensors and a gravity-measuring instrument to examine the area. Cameras will also capture images of the lunar surface and the exposed interior walls of the pit.
Scientists will combine data from these instruments to determine whether empty spaces or underground passages exist beneath the Marius Hills Pit and whether it may be connected to an ancient lava tube.
Planetary Science Institute Director and CEO Amanda Hendrix said the project represents the kind of important scientific investigation for which the institute was established. She said scientists have previously studied the question from orbit and are now developing a way to investigate it directly from the lunar surface.
Mission scientist Putzig said he had long wanted to bring active seismic techniques back to planetary science. Similar active seismic surveys were last conducted on the Moon during the Apollo era.
Scientists believe lunar lava tubes may have formed billions of years ago when volcanic activity was much stronger. Flowing lava could have created underground tunnel-like structures that later hardened and remained preserved beneath the lunar surface.
Such structures could be important not only for understanding the Moon’s volcanic history but also for future human exploration. Underground formations could offer greater protection from extreme temperature changes, small space debris and solar and cosmic radiation than the exposed lunar surface.
If GIMLI confirms the presence of a lava tube beneath the Marius Hills Pit, the discovery could provide new information about the Moon’s volcanic and thermal history while also helping scientists assess the potential for natural underground shelters for future long-term human settlements.
