A cave discovered on the Moon opens up new possibilities for human settlement

Almost 55 years after the launch of Apollo 11 – the first mission to land humans on the Moon – scientists have found evidence of a large cave system near the landing site of those astronauts.

Using radar images taken by NASA’s Lunar Reconnaissance Orbiter spacecraft in 2010, researchers have been able to determine that large craters, found in images of the moon, may actually be “skylight” in huge caves and tunnels that lie beneath the lunar surface.

These could be incredibly valuable to future astronauts hoping to land on the Moon, acting as a suitable shelter for a lunar base.

The cave is accessible through a hole in the well-studied Mare Tranquillitatis (Sea of ​​Tranquility). This is a large basin made mostly of basalt. Neil Armstrong and Buzz Aldrin landed in this region on July 20, 1969.

While Mare Tranquillitatis is unlikely to be the first place humans attempt to settle on the Moon, the existence of one cave makes the existence of others highly likely, so scientists now expect there to be others in more suitable locations. human habitation.

Mare Tranquillitatis is not scientists’ first choice for a human base because it lacks one of the other important ingredients needed for survival. There is no ice on the lunar equator and therefore no easy access to water for astronauts to drink, produce oxygen and separate for rocket fuel. This makes the equator great for landing and sightseeing, but a poor choice for setting up camp.

Ice likely exists at the lunar poles, however, thanks to the shadow that protects it from the sun’s harsh rays. So the poles are our first choice for starting a lunar settlement as it reduces the amount of water we would need to take with us.

The vent studied here is known simply as the Mare Tranquillitatis crater and is one of about 200 known vents on the lunar surface. It was first photographed in 2010 and was suspected to be a pit leading to a cave or tunnel system, but we had no way of confirming this until now.

In a paper published in Astronomy of Nature, Leonardo Carrer, of the University of Trento, Italy, and colleagues report evidence that this pit does indeed lead to a cave below, and possibly to a larger system of tunnels and canals. The Mare Tranquillitatis crater is about 100 meters (330 feet) wide, with steep walls that extend between 130 and 170 meters, making it the deepest known lunar crater.

By re-analyzing the radar data and using computer simulations to reconstruct the holes, the scientists were able to determine that some of the radar reflected back to the satellite came from an underground cave channel that is at least tens of meters long. This suggests that the Mare Tranquillitatis pit leads to an accessible cavern beneath the surface of the moon.

Exciting prospect

This discovery is incredibly exciting, not least because it is a potentially promising site for future lunar shelters and bases. In addition to providing natural shelter from harmful cosmic rays, a cave system also provides a stable temperature.

The temperature of the lunar surface fluctuates wildly over a period of weeks due to the lack of atmosphere to retain heat. During the lunar day, temperatures can rise to 121°C (250°F) in sunlight, then drop to -133°C (-208°F) after nightfall. The shade of an underground cave system is expected to regulate the temperature to be much more consistent, making it much easier to build a shelter within them.

Similarly, small asteroids often crash into the Moon due to the lack of atmospheric shielding. Being in a shelter that is strong enough to survive an impact is important. A cave provides the perfect solution for this.

While having a cave to shelter in could reduce the amount of materials we need to take to the moon to begin settling there and have a long-term human presence, there are still some hurdles to overcome.

For example, the walls of the pit are a steep drop and are over 100 meters high, meaning that future explorers will need to find a safe way to descend into the caves and climb up when they are explore the surface.

This can take the form of ladders, or more complicated systems similar to aircraft packages. Fortunately, however, the lower lunar gravity means that this problem is less severe than it would be on Earth. The structural integrity of the caves will also need to be assessed before we go inside.

The study also found that the underground system could be between 30 and 80 meters (98 to 262 feet) long and about 45 meters (148 feet) wide. That would make it big enough for several “lunar houses”. The floor also appears to be flat enough to build without any major work or preparation.

The most likely cause of lunar caves is that they are old lava tubes. These are tunnels that were formed when the moon was still volcanically active millions of years ago. Flowing lava can develop a continuous, hard crust, forming a roof over the still-flowing lava flow. A cavity then exists as the lava stops flowing.

Even better than the cave in Mare Tranquillitatis, would be the discovery of other such structures near each of the lunar poles. Astronauts would then have the best of everything – a shelter against harsh lunar conditions and access to the water ice that exists in shadowy craters at the lunar poles. This would be an excellent chance to reduce the cost and difficulty of settling on the Moon for an extended period.

The fact that we can spot them from space also allows us to plan missions to use these natural shelters. It could mean that future astronauts live in volcanically formed caves on the Moon.

This article is republished from The Conversation under a Creative Commons license. Read the original article.