NASA is still thinking about the ideal landing spot for its next manned mission to the Moon, just like the one for its future base camp. This area should in particular favor access to sunlight while bringing astronauts closer to the various sources of water ice.
As everyone knows, NASA plans to rest its feet on the Moon in 2024 as part of its Artemis program. New President-elect Joe Biden may soon relax that timeline and give the US agency an extra year or two to achieve that goal. However, in the meantime, the program is still running its course. Among the many technical challenges still to be met, there are also many questions, including that of the place of landing. And given the needs of the Artemis program, this choice will not be easy.
To date, we have only one certainty: future lunar explorers will land at lunar south pole. This is obviously no accident. The polar regions of the Moon indeed contain a precious resource: frozen water. And remember that the detection and recovery of this water is a key scientific objective of the Artemis project. Eventually, it could be transformed for consumption or to make rocket fuel.
Nevertheless, the area is large. So what are the different criteria to take into account?
Find the right balance
Given this need for water, mission planners are currently evaluating possible landing points and locations for base camp. And there, everything is a question of balance.
As NASA explains in a recent communicated, the chosen destination should indeed be sufficiently bathe in sunlight so as to be able to supply the base camp, but also to allow easy access to water ice rich areas. Finally, ideally, this location should also offer moderate temperature variations.
It turns out that the Moon’s rugged topography should be able to provide such a location. NASA indeed thinks that it might be possible to land along the edge of an impact crater.
From there, astronauts will be able to benefit from the sunlight. Remember that unlike the Earth, the Moon is very slightly tilted (1.5 degrees on its axis). Also, for astronauts in polar regions, the height of the Sun would remain largely the same over the course of a day. As NASA says, if “a person would stand on a hill near the lunar south pole during the day, at any time of the year they would see the sun moving on the horizon, brushing the surface like a flashlight on a table“.
On the other hand, this location located on the edge of a crater would also allow access to areas perpetually in the shade, inside this structure, where the lunar water ice is located. It remains to be determined which border will work best.
Distinguish between landing zone and base camp
It should also be noted that the landing point must be reasonably far from the main activity area. This is because the propellants of the lander will project huge amounts of material in the form of dust and rocks. The craft’s thrusters will also contaminate the immediate area. This is the reason why the base camp, which will include housing and solar panels, must be located at at least 800 meters from the landing site.
Finally, this same landing point should be located on the side of the Moon facing the Earth, so as to facilitate communications with ground controllers.