How to Build a City on the Moon

The new head of the European Space Agency wants to give it a try.

Image AP Photo/Julio Cortez
AP Photo/Julio Cortez

Humans haven’t set foot on the moon since 1972. That hasn’t stopped Johann-Dietrich Woerner, the new director general of the Paris-based European Space Agency, from pushing mankind toward more of a giant lunar leap than another small step. Woerner kicked off his tenure by telling BBC he not only wants to go back to the moon but hopes to build a village there—on the far side, no less.

The very idea of a moon city ignites a constellation of questions about what it would look like and how we would build it. So CityLab called Woerner to find out. With the International Space Station potentially coming offline around 2024, he says, it’s time to envision the next era of human presence beyond Earth. The moon-city project would be a prime driver of technological advancement as well as basic scientific research.

“Why not have a moon village?” says Woerner. “A moon village not meaning a few houses, the town hall, and a church—the moon village would consist of a settlement using the capabilities of different space-faring nations in the fields of robotic as well as human activities.”

Building in space

To succeed, lunar architects must turn the moon from a design challenge into an asset. For starters, the moon offers natural shelter in the form of a couple hundred steep-walled pits that NASA’s Lunar Reconnaissance Orbiter spotted on the surface. Scientists think these pits could protect astronauts from environmental risks like micro-meteoroids, solar radiation and titanic swings in temperature from 253 degrees Fahrenheit by day to -387 degrees at night.

Luckily the moon’s rocky soil, called regolith, is abundant and works pretty well as insulation. Humans could use it to construct their lunar houses, Woerner says. They will need a glue to bind it together into “moon concrete,” though, so one task will be figuring out if that can be made onsite or if it needs to be carried from Earth.

Light-weight modules like the space station’s Columbus lab might serve as building blocks for a moon village. (ESA)

Participating space agencies would probably send robots to do the advance work before people arrive. Woerner hopes the building process will feature strong international collaboration. When it comes time for construction, those involved should take a diversified approach, writes Bernard Foing, director of ESA’s International Lunar Exploration Working Group, in an email. He recommends a mix of light-weight rigid modules like the space station’s Columbus lab, inflatable units, and some 3-D printing technologies.

America’s role remains an outstanding question. Back in 2006, when NASA was heavily planning a moon settlement, the strategy was to launch multiple weeklong landings by astronauts to deliver parts for a base suitable for longer stays. But NASA dropped out of the lunar settlement game after the Obama Administration cut funding for the Constellation program in its budget proposal for 2011. Now NASA is playing more of a supporting role with lunar endeavors, like assisting commercial development of lunar landing capabilities through the CATALYST program.

That leaves an opening for other organizations to take the lead, either from private industry or the rest of the world.

Surviving in space

A moon village must include habitation units, laboratories, power generators,  facilities for processing lunar water and resources, a manufacturing workshop, and a greenhouse, notes Foing. The operation would be rounded out with a pressurized moon buggy, assets in lunar orbit for access and communications, and a landing facility, not to mention whatever robots prove useful.

Successful agriculture would be a major boost to a sustainable permanent settlement, since astronauts wouldn’t have to rely on food shipments from Earth. A farming study last year found 20 percent of crops grown in simulated lunar soil survived 50 days—not a bountiful harvest, but not an unmitigated disaster, either.

The “dark side” of the moon actually gets as bright as the side seen from Earth. (Paul Lockhart / Flickr)

And before you start worrying about the poor astronauts forced to live shrouded in eternal darkness, Woerner points out that the popular concept of the moon’s far side isn’t quite right. “It’s not the dark side of the moon as Pink Floyd was thinking,” he says. “The far side of the moon—the hemisphere of the Moon that always faces away from Earth—is as bright as the side of the moon we see. You know that sometimes during a month the moon is dark. At that time, the other part of the moon is very bright.”

In fact, Woerner adds, locating the base on the far side would aid in telescopic observations because the body of the moon would physically shield an observatory from the Earth’s radio waves.

Visiting Moonland

Once mankind has established a foothold on our nearest celestial body, the next task will be figuring out what exactly to do there. The first astronauts will have their hands full constructing the village and conducting lunar research, Foing says, but they will have at least one perk: “a magnificent changing view of the spinning Earth,” which will look four times larger than the moon and more than 50 times brighter.

If that giant glowing Earth makes them homesick, the astronauts-in-residence can turn to a local art museum. A team of artists and engineers at Carnegie-Mellon University have designed a “Moon Arts Ark” that will use advanced nano-art techniques to compress an overview of human cultural achievement into a pod half the size of a Coke can. The capsule will catch a ride to the moon along with a robotic rover in 2016, leaving plenty of time to get set up before the first human visitors arrive.

Eventually, Woerner predicts, professional astronauts won’t be the only people on the moon. “Our work is to do research, science and development, but I’m quite sure—as we saw happening here on Earth—that tourism will follow exploration,” he says.

Earthly industry may take an interest, too. It’s possible that resources found on the moon—like helium-3, rare earth metals, and crashed asteroid debris—could have commercial uses back home, though Woerner notes that the expense of transportation to and from the moon will make it hard to turn a profit for the foreseeable future.

That’s a long way off. For now, says Woerner, developing the moon village will be challenge enough.

“It’s not out of reach, as it was not out of reach in the late ‘50s of last century to go to the moon,” he says. “Of course, there are many developments necessary for that. But I think from a feasibility point of view it is feasible, it is visionary, it is demanding. In general, it should be possible.”

About the Author

  • Julian Spector is a former editorial fellow at CityLab, where he covers climate change, energy, and clean tech.