The moon is finally receiving the attention it deserves

The Chinese lander Chang'e-4 and his little rover, Yutu-2, were observed by Lunar Reconnaissance Orbiter of NASA in February. Note the movement of Yutu-2 between the frames – the first surface exploration on the other side of the moon. (NASA / GSFC / Arizona State University)

We have reached another "will they do it or will they not?" In the long-running soap opera, When will humans return to the moon? Last May, NASA's administrator, Jim Bridenstine, promised that a crew would disembark by 2028. "For many, this may look like our previous attempts to reach the moon," he said. he admitted. "However, times have changed. It will not be Lucy or football anymore. A month ago, Vice President Pence added a new type of conspiracy, now stating that "this administration and the United States have a policy of returning to the Moon of American astronauts for the next five years. "

A return to the moon from here 2024? In spite of the bold rhetoric, it is at best a weak "maybe".

Unofficial sources estimate that achieving the Pence goal will cost about $ 40 billion over five years, double the NASA annual total budget. Congress should approve these expenditures, and so far, there is no obvious political support. But even if human exploration is launched in the future, the robotic exploration of the moon is taking off – and it is there that the drama becomes real and really interesting.

Although NASA has not been present on the surface of the moon since the 1970s, it has enjoyed a decade of extremely successful presence. around the moon with lunar recognition orbiter (LRO). China has been busy on the moon: Chang'e-3, its first lunar lander, landed in 2013, and Chang'e-4 is currently conducting the first surface explorations of the dark side of the moon. Beresheet, created by SpaceIL, an Israeli non-profit organization, almost became the first private mission on the moon three weeks ago. It was derailed by a software control error that occurred 14 kilometers from touchdown.

There is still much to be done on the robotic side of the story. The SpaceIL team has already started working on Beresheet 2, drawing on the lessons learned from their near-success. India is currently working on Chandrayaan-2, a lander and rover that could be launched as early as this month. China has at least four other Chang'e lunar landings, including examples of return missions, to build a solid lunar robot infrastructure before sending astronauts (or rather taikonauts) in the 2030s. and the European Space Agency have their own concepts under development, although their funding is uncertain.

The phases of the dark side of the Moon have been reconstructed from observations made by NASA's LRO satellite. Such a view is impossible from the Earth; we are the first species to see it. (Credit: NASA's Scientific Visualization Studio)

The great hope (for future space contractors as well as for space exploration enthusiasts in general) is that the private sector is helping to expand opportunities by reducing costs. The first step, which is well advanced, is to develop less expensive rockets and spacecraft. The second step is to develop technologies to use local resources on the Moon: "in situ resource use" or ISRU in industry jargon. ISRU could mean extracting ice from the lunar soil to make a rocket booster; it could also mean the creation of habitats and the accumulation of water and oxygen reserves for the magic moment of astronauts' return.

A series of successful robotic missions could be the critical element that will ultimately enable these human missions to come true. China is betting explicitly on this strategy, and NASA is implicitly betting on it as well.

In addition to reducing the cost of exploring the human space, robotic missions should clarify the value of returning to the moon. I will not go into the fundamental question of whether to spend money on space exploration (I've already mentioned many other places, like here.) If you believe, like me, that space exploration is worth the modest sum that our society spends in it, then the relevant question is whether we have important things to learn by returning to the moon.

In this case, the answer is extremely simple: yes, we do it. The moon deserves our attention and deserves much more attention than it has received in recent decades. A stream of recent discoveries proves it very clearly.

NASA's LRO has shown that the moon is full of complex and fascinating geologies. It has ice deposits (probably well mixed with lunar dust) in craters permanently shaded near its poles. It shows signs of surprisingly recent volcanic activity. Small impacts recycle the lunar surface much faster than predicted by researchers. LRO's camera captured the formation of more than 200 new craters on the moon. We now know that many of these impacts produce easily visible lightning from the Earth, such as the one that appeared during the lunar eclipse of January 2019.

A brand new 12-meter-wide crater that formed on the Moon in late 2012 or early 2013. LRO observed more than 200 of these new impacts, providing a direct measure of the local threat related to asteroids. (Credit: NASA / GSFC / ASU)

The recording of old craters on the Moon also indicates that the significant impact rate has increased from about 290 million years ago, probably due to a collision in the asteroid belt. The course of evolution on Earth, from the rise of the dinosaurs to the present day, has been shaped by such impacts; on the Moon, we can see the complete recording, not obscured. The impacts also transport materials between the Earth and the Moon, which means that much of the Earth's earliest history could still be preserved there. (See my recent post.)

In a broader perspective, it is truly strange that we have given so little attention to the planetary world sitting before us in space, less than 1 / 100th of the distance that separates it from Mars. Moon and Earth were formed together; its history is our story, and yet the details of this story are still largely locked up, unread, on the lunar surface. A deeper inventory of lunar rocks would also answer many more general questions about the formation of the solar system; he could test the theory that Jupiter migrated to the Sun, then move away from the Sun, and that at least one giant planet was driven out of the solar system at the beginning of its chaotic phase.

If we want to become space species, to learn to live and to explore far from the Earth, it is natural for us to start with the world closest to us. If we want to develop ways to use local resources and develop defenses against the intense radiation of space, the Moon is the obvious training ground. "Will they or will not they?" Is a question for this year and the following year. "What are we going to learn there?" Is a question for ages.