The discovery of a colossal lava tube near the Apollo 11 landing site is opening up possibilities for utilizing such “skylights” to establish a Moon base in the near future.
Caves were the first shelters for humanity. Who knows what our distant ancestors thought while seeking refuge there, gathering around a fire to cook meat, and painting animals on the walls? Caves protected our ancient ancestors from natural elements, predators, and rivals, during a time when sticks, stones, furs, and fire were our only technologies.
Thus, there is a poetic parallel between primitive humans and us today. We have visited the Moon, and the caves there could shelter us just as caves sheltered our ancestors on Earth.
A stunning view of a 100-meter “skylight” in the Mare Tranquillitatis region, which is a lava tube on the Moon. (Photo: NASA).
On the Moon, astronauts will need protection from various dangers. They will face cosmic and solar radiation, meteoroids, sudden temperature changes, and even impacts.
The Lunar Reconnaissance Orbiter (LRO) has discovered hundreds of “skylights” on the Moon, which are collapsed lava tubes that create a natural cave opening to the planet’s surface. These lava tubes can be several hundred meters in diameter, potentially providing ample living and working space, a shelter that astronauts will require. The idea is to establish a permanent base within such “skylights” on the Moon.
According to El Pais, a group of Italian astronomers from the University of Trento has recently published a detailed analysis of one such “skylight” on the Moon. They estimate that the large chamber inside the cave could extend 100 meters, lying deep beneath the surface.
In fact, lunar caves are not a new discovery. Half a century ago, Verne Oberbeck, a planetary scientist hired by NASA, hypothesized their existence. The first cave was identified in 2009 thanks to images sent back by Japan’s Kaguya probe. Subsequently, other satellites, especially the Lunar Reconnaissance Orbiter, added many more caves to the catalog. Today, over 200 lunar “skylight” caves have been discovered.
Lava tubes could become natural shelters and bases for humans on the Moon. (Photo: NASA/universetoday).
The cave currently being studied by the Italian scientists is actually a gigantic pit with a diameter of 45 meters. When the sun shines directly overhead, the bottom of the cave can be observed, 150 meters deep, covered in rock.
“This gigantic skylight” is located in Mare Tranquillitatis, about 400 kilometers from where Apollo 11 landed. Its origin is believed to be due to the collapse of a lava tube, a remnant of molten material that occurred in a very distant era when the Moon’s plains were still young. Such formations are also found in volcanic regions on our planet.
The walls of the Tranquillitatis cave appear to have been cut with a tool. Lowering a vehicle into it would require something akin to a crane. Meanwhile, other caves have slopes of about 45 degrees, too steep for wheeled rovers to navigate. However, alternatives exist: a hopping robot could easily explore such deep caves.
The work of the Italian astronomers is based on radar data obtained by the LRO over five years ago. The recordings used to collect data can be stored for long periods until someone needs them for specific research. By running various simulations, the researchers concluded that this cave could extend an additional 50 to 80 meters.
This cave is the size of an Olympic swimming pool. If this is accurate, it would be an excellent structure for establishing a shelter for future astronauts. At that depth, they would be safe from meteoroid impacts, and the bombardment of cosmic rays would be significantly reduced. Additionally, similar to caves on land, minerals would help regulate temperature differences between day and night.
The authors of the study note that the accessibility of the cave and its slope promise the establishment of a Moon base. They also emphasize that such geological formations could be crucial for lunar missions due to the extremely harsh surface conditions of this celestial body, with temperatures ranging from 127°C to -173°C, alongside high levels of cosmic and solar radiation. Therefore, finding safe locations for infrastructure, such as these caves, is essential for sustaining exploration activities.
Image of the entrance to a lava tube on the Big Island of Hawaii. (Photo: Wikimedia Commons).
NASA has considered the possibility of establishing a future base by covering its walls with a thick layer of regolith (moon dust). Previously, China also hinted at this option, but no specific plans have been announced yet.
About six months ago, a video was leaked from the China National Space Administration, revealing details about the country’s lunar conquest plans. The plan involves using magma tubes to create habitable underground modules, with inflatable structures lined with insulating materials by robots. The plan also mentions building an orbital station around the Moon to control exploration and rescue operations by robots.
The video also discussed the possibility of drilling tunnels on the Moon’s surface by launching rockets from lunar orbit. This hypothesis sounds more like science fiction than reality, but we are talking about a long-term plan, where China may collaborate with Russia on launching and constructing the International Lunar Research Station in the future.
In the spring of 2023, China announced plans to begin building a base on the Moon by 2028, though it is unclear whether this announcement refers to a lava tube-based base. This plan seems to contradict the most recent statement indicating that China plans to “land humans on the Moon by 2030.”
Regardless of when they start, China appears committed to this idea. Ding Lieyun, a leading scientist at Huazhong University of Science and Technology, told the China Science Daily that: “Ultimately, building a residence beyond Earth is essential not only for the space exploration journey of all humanity but also for China’s strategic needs as a space power.”
