Space rock showers, poison dust, killer radiation next to zero atmosphere—the moon seems inhospitable until you look into its past.
Mars is the obvious first choice for future space colonization. Though the Red Planet hardly has more of an atmosphere than our moon and is incessantly bombarded with cosmic radiation, the hype mostly comes from the prospect of exploring a planet we’ve never put boots on before. There are already footprints on the moon. We’ve brought back moon rocks and moon dust. But. NASA has recently found evidence that our satellite once had an atmosphere, and that could make it that much more attractive for anyone looking to get off this planet.
After the inner solar system emerged billions of years ago, huge space rocks smashed into the nascent moon and planets during the period known as Late Heavy Bombardment (LHB) or the lunar cataclysm. These rocks not only left behind gaping craters on inner planets and the moon but set off violent volcanic eruptions. As lava loaded with volatile molecules oozed across the moon’s surface, the hydrogen, oxygen, sulfur, and carbon monoxide that were released formed a proto-atmosphere.
What is thought to be trillions of gallons of water escaped from lava flows during 70 million years of eruptions. This water and other volatiles either stayed on the moon or floated out to space, and much of it could have settled in the lunar poles and still lie undiscovered in the shadows of the moon’s far side (often referred to as its dark side because it is in permanent shadow). Based on samples brought back from the Apollo missions, NASA researchers have been able to figure out quantities of volatiles that could be sources of water, air, and fuel. Astronauts could use these resources whether they will be staying on the moon for a while or using it as a way station to Mars.
Enough of those volatiles could mean that what start out as astronaut habitats could expand into entire colonies that will depend on those resources. We absolutely can’t live without water and breathable air. Fuel that will potentially power everything from electronics to spacecraft can be processed by splitting water into its hydrogen and oxygen components. Of course, we’re going to need a number of moon missions to actually confirm that volatiles actually exist in such quantities, but it looks like NASA is on to something.
If it turns out that the moon really is hiding enough volatiles to make it a habitable place, there are already so many habitat prototypes for Mars that figuring out lunar living shouldn’t be a problem.