Is the moon best left alone?

I'm not exaggerating when I say that our studies of the moon have unlocked the mysteries of the universe.

Simply put, the moon is useful in a way that no other astronomical object is. That's because it's the nearest, most easily accessible entity that is not Earth. If we want to understand everything from the formation of the solar system to the deepest nature of gravity, the moon is our best bet.

Heck, we didn't even go there for millennia and we still learned a lot. One of the earliest pieces of evidence that Earth was round came from lunar eclipses.

The shadow our planet casts on the moon is always circular, which would be impossible if the Earth was a flat disk. When Galileo first gazed at the moon with his homespun telescope in 1609, he immediately recognized—thanks to his background in painting and perspective—that the dark corners and edges on its surface were shadows caused by mountains, proving that the moon was a three-dimensional object, not a flat polished disk.

And nearly a century later as Newton was contemplating the nature of gravity, he realized that the force that pulls an apple from a tree is the exact same force that keeps the moon in its orbit around Earth, unlocking gravity as a universal force of nature.

Once the Apollo missions brought back the first lunar samples, however, we really got going. Those missions, despite each only lasting a day or so on the lunar surface, resulted in more than 3,000 scientific papers published.

Perhaps the most astonishing result was that lunar regolith, the dirt that covers the surface, contains many of the same radioactive elements as Earth's crust, in many of the same proportions. This was a huge piece of evidence for the giant impact hypothesis, that four-and-change billion years ago the proto-Earth was struck by an object the size of Mars that mostly buried itself in our own planet, but also threw up material to create the moon.

Today, we treat the moon as a time capsule. It's a relatively untouched, pristine environment that records a memory of that event. Soon after the moon was created, it cooled off and solidified, and it's basically been the same since. By digging into the moon, we learn about what life was like at the very dawn of the solar system.

But the moon hasn't been completely static in all that time. Impacts from asteroids and comets big and small have left their mark on the surface, and the size, positions, and even shape of all those craters tell us about the dynamics of the solar system over the course of billions of years. We use that kind of cratering record to determine, for example, how efficiently comets delivered water to the early Earth. If we want to understand how we got our oceans—and our life—the moon has the answer.

Many nations have many active sensors and detectors on the lunar surface or in orbit, like NASA's Lunar Reconnaissance Orbiter, which is currently mapping where water ice might exist on or near the surface. All these instruments give us a portrait of an alien world, one that formed right next to us but followed a completely different trajectory in evolution. If we want to understand how small worlds evolve in systems across the galaxy, the moon has the answer.

Check this out. The sun is constantly emitting a stream of tiny, charged particles, called the solar wind. That solar wind burrows itself into the regolith, where it leaves tiny little holes, and can change the chemical composition of the molecules found in the regolith. Take up a scoop of lunar dirt, and you can read off billions of years' worth of solar activity. If you want to understand what the sun was up to billions of years ago, and how that might have affected, say, the evolution of life on Earth, the moon has the answer.

The thing is, lunar science is just getting warmed up. We've only been able to touch, smell, and taste—you know someone's done it—the moon for a little over half a century. There is so much we have yet to learn about the moon, I could devote an entire episode to it—and I just might. We have near-term goals, like building better maps of the interior to better understand how it formed, to mapping the chemical composition of the various regions on the surface to better understand how geophysical processes operate in low-gravity, airless environments.

And then there are the surprises, the things we have yet to learn because we don't have the tools, techniques, or expertise to even begin asking the questions. I'm not saying we're going to, I don't know, find life buried under the surface (even though that would be awesome), but the moon has much to teach us. Increased industrial activity on the moon puts this all at risk. For example, we might find a crater in the south pole that's shielded from the sun and has water ice on the surface, and that would make the perfect spot to investigate the nature of the moon even further. Oh, nope, sorry, we can't do it, because now there's a moon casino there.

Yes, I know that the moon is big. The lunar surface has a total area slightly smaller than the continent of Asia, and last time I checked, Asia is really, really big. And there are lots of places in Asia that are developed or industrialized, and there are plenty of spots that are the subject of intense scientific research or under protected status.

But with the moon, we don't know which places are the best for science yet, and if we always let private development come first, with anybody with an itchy launch finger given free rein to go wherever they want and do whatever they want. We already know that we've made many mistakes in the past on Earth with that kind of loosey-goosey attitude—just look at how we KNOW that the deforestation of the Amazon rainforest is causing us to lose knowledge of potentially beneficial pharmaceuticals before even get to know about it. We don't need to repeat those mistakes again.

We even have a framework for doing this right! In 1948 the United States proposed that Antarctica should be held under the guardianship of the United Nations. By 1961, the first of the Antarctic treaties were signed into law by many nations. Among other things, the treaty prohibits nations from building military bases on the continent and testing nuclear weapons. And while many nations have claims to Antarctic territory, the treaties put them on hold until some indeterminate time in the future.

And most especially, the treaty bans all commercial mineral resource activity. No digging, no mining, no fun. Well, you can have science fun, but that's it.