(seventh in a series)

Another invaluable lunar resource is energy. One side of the rotating Moon is always bathed in sunlight. If you’re near the equator, as at the Apollo 11 landing site, the Moon’s rotation would give you two weeks of sunlight and then two weeks of extreme cold and darkness. At the south pole, at the Moon’s rotation axis, the sunlight strikes the surface at a very shallow angle, slanting in from around the compass over the course of 28 days.

There are elevated spots near the lunar poles where the low-angle sunlight produces nearly continuous illumination. For example, at the circular crater called Shackleton, the oblique sunlight lights up part of the elevated rim, with the sun shining about 90 percent of the time. Thus, near the pole, you could set up a solar panel and produce power nearly all the time—a much better situation than at the equator, where one must store enough electricity to last through two weeks of darkness.

A video here shows the varying illumination over the course of a single lunar month; much of the high terrain at crater rims remains sunlit for more than three weeks out of a month.

In this map of the lunar South Pole (below), the brighter tones show the greatest illumination over the course of a whole year (2026). The darker tones mean that sunlight is much reduced. But notice the bright rim of Shackleton, which is bathed in nearly continuous solar energy. Here on Earth, a rooftop solar panel will produce no electricity for roughly 12 hours out of 24. At Shackleton, you’d enjoy nearly round-the-clock illumination and power. Elevated crater rims, as at Shackleton, would be a very good spot to set up solar panels to power a base or operate a refinery turning water ice into fuel and life support gases.

The Moon’s polar resources, then, include water ice and sunlight, two attractive  ingredients located close together at the sunlit rims and the adjoining shadowed crater interiors. As discussed earlier, the Moon’s familiar minerals can be used right away as construction materials: bricks, panels, walls, or radiation shielding. But down the road, the Moon’s more exotic elements and compounds are of interest.

The regolith contains elements like iron, very easy to separate. By dragging a magnet through the dirt, you’ll retrieve a lot of native iron carried in by meteorite impact. Thorium, a radioactive element, is an attractive fuel for nuclear fission reactors, enabling the fission process to make more fuel than it consumes. We might imagine the prospect in this century of importing reactor fuel to Earth from the Moon.

Another promising nuclear fuel is He-3, helium three, a rare isotope of helium. Its use in fusion reactors would enable a cleaner fusion reaction and moderate reactor temperatures. Advocates have proposed sifting and mildly heating the Moon’s regolith at large scale to extract enough helium-three to fuel those future nuclear fusion reactors, generating electricity here at home. Another He-3 application is as a coolant to chill quantum computing chips to temperatures near absolute zero, where they are fastest and most efficient.

Earth’s crust contains little He-3, and any of this light helium released from Earth rocks was able over the past four and a half billion years to largely escape from Earth’s atmosphere. In Earth’s mantle, the ratio of He-3 to He-4 (the most common He isotope) is only about 20 parts per million, and that extracted from crustal natural gas is some 70 to 240 parts per billion (roughly a thousand times lower). But on the Moon, He-3 is continually implanted into the regolith’s upper few meters by the solar wind. It’s present at a concentration in sunlit regions at up to 15 parts per billion—still not very plentiful.

Yet with current prices of about $20 million per kilogram, companies like Interlune see lunar helium-three as an attractive natural resource, one justifying a mining operation that would eventually sift a million tons of regolith to recover tens of kilograms of the isotope annually for return to Earth.

The value of lunar He-3 depends on demand from quantum computing, and our ability to design practical fusion reactors—none exist today. Commercial fusion reactors always seem to be 20 years in the future.

That horizon reminds me of my astronaut career, during which a return to the Moon has always seemed 20 years in the future, too. But the Japanese and Chinese have also indicated interest in exploring the economics of eventually extracting helium-three from the Moon. If the mining and extraction process proves profitable, and we do manage to create fusion reactors to use helium-three, our energy supply problems are over. No more worries about carbon emissions, no more worries about mining fossil fuels, and a much-reduced nuclear waste challenge. Fusion would be a limitless energy source. But the promise of He-3 is many years from being realized.  

Next: Why Send Humans Back to the Moon?

www.AstronautTomJones.com

(sixth in a series)

The third reason for going back to the Moon is that it is useful. Water is the first of the resources on the moon we will tap—it’s like gold in space because of its scarcity outside Earth’s hydrosphere and atmosphere. If we can tap the Moon’s natural water, we can supply astronauts with drinking water, and they can breathe the oxygen released from water when electrolyzed. By storing hydrogen and oxygen from the Moon’s water, we will stockpile rocket fuel for lifting off the surface or filling the propellant tanks of craft headed outward into the solar system.

Water is present on the arid Moon today because the floors of many craters at its poles are in near-perpetual darkness, protected from the slanting sunlight by the raised crater rims. The shadowed floors of these craters radiate their heat directly to space and thus get very cold: below minus 300 degrees Fahrenheit. And as comet ice and water-rich asteroids have struck the Moon, their violent impacts vaporized rocks, liberated the water and created an ephemeral temporary lunar atmosphere, including that water vapor. Water molecules then migrated to and got stuck in those polar cold traps–the molecules condense onto the surface. That 4 billion years of accumulated impact water, along with implanted hydrogen from the solar wind, comprises a reservoir estimated at hundreds of millions of tons.

In this image of the polar regions of the moon, the light blue dots show water ice deposits—the hydrogen, actually—detected from orbit by satellites. Water ice, when melted, can be broken down further by electricity into oxygen and hydrogen. Those elements are a powerful rocket fuel combination—hydrogen as the fuel and oxygen as the oxidizer. The next steps are to characterize in what form these water deposits exist inside the dark craters, and then test processes that can liberate the water for use in an outpost.

Let’s not forget the Moon’s dirt. The lunar soil has very useful properties that explorers can use to advantage. The Moon’s soils can be used as construction materials like bricks, panels, walls, or radiation shielding, moved and shaped by bulldozers or compressed into molds. Using a lawn-mower-sized microwave transmitter, a lunar paver can sinter the moon’s regolith, fusing the tiny iron particles mixed up in that dirt into a hard pavement. A robot paver could lay down a dust-free landing pad or a roadway for a cargo delivery rover.

Here is a Northwestern University image of some simple tools, resembling Legos, made by a 3D printer from simulated lunar dust (the gray material) and simulated Mars regolith (in orange). This 3D printing technology (using a biopolymer binder) is getting better and more advanced every year. Another idea is to extract native iron from lunar regolith using electromagnets; with that iron, a small steel mill can produce beams, wires, struts, and structures for habitats and industrial mechanisms.  

After we build the first key elements of a lunar outpost, the moon’s more exotic elements and compounds are of interest. Blue Origin is conducting research aimed at using solar or nuclear energy to melt and electrolyze lunar regolith, liberating oxygen from the melt and extracting various metals like titanium, iron, and aluminum. The company’s Blue Alchemist project aims to transform regolith into solar power systems, breathable oxygen, propellant-grade oxygen for refueling, metals, and construction materials. Tests of the regolith melt process are underway in the company’s labs.

Next: The Moon’s Useful Energy Resources

www.AstronautTomJones.com

In late August I talked with NewsNation on the accelerating competition between China and the U.S. to return to the Moon. NASA plans to speed up deployment of a lunar surface nuclear reactor, to power an outpost and resource extraction, are a good step forward, but the administration should be strongly supporting the Artemis lunar return missions, with a ~2027 lunar return on Artemis III (a stretch as the effort stands now). All China has to do for a “W” is to duplicate Apollo 11, while we attempt a much more ambitious lunar return with more people, longer stays, and long-term infrastructure. But greater complexity plus static budgets mean “slow.” Perceptions of global tech superiority matter; we need to change that pace–quickly.

My comments here (note–the nuclear commenter in the clip is incorrect; NASA is building a fission reactor):

https://www.youtube.com/watch?v=M0vOF89mLT0

In late August I talked with NewsNation on the accelerating competition between China and the U.S. to return to the Moon. NASA plans to speed up deployment of a lunar surface nuclear reactor, to power an outpost and resource extraction, are a good step forward, but the administration should be strongly supporting the Artemis lunar return missions, with a ~2027 lunar return on Artemis III (a stretch as the effort stands now). All China has to do for a “W” is to duplicate Apollo 11, while we attempt a much more ambitious lunar return with more people, longer stays, and long-term infrastructure. But greater complexity plus static budgets mean “slow.” Perceptions of global tech superiority are important; we need to change–quickly.

My comments here (note–the nuclear commenter is incorrect; NASA is building a fission reactor):

www.AstronautTomJones.com

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