HELSINKI — Chinese researchers are taking a serious look at detecting and utilizing lava tubes on the moon as China plans its development of an extensive lunar base.
China is leading the International Lunar Research Station (ILRS). The project envisions a basic robotic south polar base built by five missions across the early 2030s. An extended ILRS would include an expanded base, as well as an orbital station and nodes elsewhere on the moon. The latter will be capable of hosting short term human stays.
A series of papers on lava tubes and their detection, modeling, the status of research and how to explore lava tubes have been published in the Chinese language Journal of Deep Space Exploration (JDSE). The issue as a whole reflects an effort to develop a systematic approach for exploring and utilizing lava tubes. These features may be involved in the ILRS project.
Lava tubes are considered ideal locations for future lunar bases, combining scientific value with potential habitation opportunities. Lava tubes provide essential shielding for crew and infrastructure from radiation and micrometeorites.
The paper reviewing the status of lava tubes in the solar system looks at formation mechanisms and their scientific significance. It calls for the first systematic detection of lava tubes on extraterrestrial bodies, use of terrestrial lava tubes as analog sites, and notes that extraterrestrial lava tubes are not only natural shelters, but may also hold the remains of ancient life.
A paper proposing an exploration and development plan for lunar lava tubes calls for multi-stage exploration. It uses Mare Tranquillitatis and Mare Fecunditatis as case studies. The plan involves mobile robots equipped with 3D imaging and navigation systems. It includes the deployment of surface rovers to explore and map the entrance of lava tubes. This will be followed by the use of smaller, more agile robots or drones to enter and explore the tubes themselves.
The article however notes a number of challenges to construction of habitats inside lunar lava tubes such as entry and exit of large equipment and personnel into the tubes. Others include modifying the natural terrain for building infrastructure, using in-situ materials for construction and ensuring the structural integrity and airtightness of lava tubes for pressurized environments.
Another article details a high-performance ultrasonic driller suitable for drilling in the inner wall of lava tubes. A further paper puts forward a lightweight mobile measurement system for the 3D mapping of lava tubes.
The papers indicate that Chinese researchers are keenly aware of the potential of lava tubes and serious about its robotic and crewed lunar plans, Clive Neal, a professor and lunar scientist at the University of Notre Dame, told SpaceNews.
“First and foremost, lava tubes represent almost ideal habitats,” says Neal. “They provide protection from micro and some macro meteoroid bombardment, the thermal swings between night and day, and primary and secondary radiation. Any habitat on the Moon must be buried several meters below the surface otherwise humans will be at a severe risk of harm.”
It also serves as a wake up call to the United States and NASA, says Neal.
“With the cancellation of VIPER, the United States has basically ceded leadership in lunar resource exploration. China has two missions going to the South Pole to prospect for lunar volatiles, with Chang’e-7 and Chang’e-8.
“China is serious about a human-tended lunar outpost. The United States does not appear to be ready to be serious about this. It is unfortunate that, unlike China, we do not have a cohesive plan for human and robotic exploration of the Moon like China has,” Neal adds.
The consideration of lava tubes in regions away from the lunar south is another hint at how seriously Chinese researchers are considering its long term efforts.
“China has figured out the enormity of burying a habitat at the south pole, or is planning to set up multiple habitats across the Moon, using lava tubes in the mare basalt regions. This alone should be a wake up call for America,” says Neal. NASA’s Artemis plans envision a “base camp” at the lunar south pole.
The United States needs to wake up because we are rapidly being left behind, says Neal. “China will get to set a precedent on how lunar resources are used because they have a plan.
“If we want to have a vibrant cislunar economy underpinned by lunar resources, VIPER should be the first in a series of rover missions, not only for water ice, but for helium-3, rare earth elements, and platinum group elements,” Neal says.
China’s Chang’e-7 mission will target Shackleton crater. It will use multiple sensors and spacecraft to assess resources at the lunar south pole. These include a hopping rover primed to seek out evidence of water-ice in permanently shadowed craters. Chang’e-8 will test, among other things, 3D printing on the lunar surface and in-situ resource utilization. The missions are scheduled to launch in 2026 and 2028 respectively. There are currently no known approved missions to explore lava tubes.
The country secured the 13th national-level partner for the ILRS last week when Senegal signed a memorandum of opportunity. China has now attracted around 40 partners including space agencies, universities and firms from Asia, Europe, Africa and South and Central America.
