Welcome To My Lava Tube, Premium Lunar Condo Living*

This 65-metre-wide hole in the lunar surface extends at least 80 metres down and could be an opening into a larger lunar cave (Image: ISAS/JAXA/Junichi Haruyama et al.)

Let’s face it, us soft and squidgy humans don’t react particularly well to radiation, the vacuum of space or hypervelocity meteoroids. This being the case, how do we ever hope to settle on other worlds, particularly worlds with dust for a backyard and a sky flooded in radiation from the Solar System’s biggest nuclear reactor (the Sun)? To put it mildly, it’s not going to be easy. In fact, exploring and settling on other celestial bodies will the the biggest challenge us terrestrials will face in the next century.

So we start thinking locally, we start thinking “familiar”; where could we build a habitat that’s a stone’s throw from Earth, where we can do a full-scale practical test of our colonizing skills but be only a couple of days from home?

The Moon is that world and we are currently stumbling our way toward that goal. In fact, it is (currently) one of NASA’s main priorities, to get man back to the Moon by 2020 (although the Augustine Commission report was released today and presents many more options for the future of NASA). Once we do eventually get back to the Moon, our lunar explorers will use man made habitats, but what about longer, more permanent settlements?

We’re going deeper underground

In-situ mining of materials for building habitats and using the landscape to protect settlers isn’t a new idea, but we are beginning to acquire better observations of the Earth’s only natural satellite. And now, observations from the Japanese Kaguya spacecraft (that was deliberately crashed into the lunar surface in June) have been used to scout out a possible location for a future permanent habitat.

Cavemen 2.0 (NASA)
Cavemen 2.0 (NASA)

It may be hard to believe, but the Moon was once a very hot body, where molten rock began to cool shortly after formation. This molten rock eventually solidified, but in doing so, lava burrowed out long channels known as sinuous rilles. These rilles are a sure sign that lava once flowed there. However, scientists have known for some time that beneath these rilles, lava tubes may also hide. The lava tubes formed when the remaining molten rock flowed away, leaving an encrusted layer of rock surrounding a closed network of tunnels.

A lava tube with a view

However, this is the first time a hole in the roof of one of these lava tubes has been found. This hole, for obvious reasons, has been dubbed “a skylight,” and Junichi Haruyama and the SELENE/Kaguya team have been working hard to seek out such features. Their hard work has just paid off.

This is the first time that anybody’s actually identified a skylight in a possible [lunar] lava tube,” said Carolyn van der Bogert, a co-investigator on the team from University of Münster in Germany, of the discovery in a region of the Moon’s near side in Marius Hills.

The skylight measures 65 metres wide and it is thought to extend 80 metres deep. The hole is right in the middle of a rille, indicative of the presence of a lava tube 370 metres across. It is currently unknown whether the skylight allows access to the lava tube (access may be blocked by rubble or solidified magma), but there is the tantalizing possibility that this hole could be used by astronauts to access an underground cave.

Anti-radiation living

Basalt is an extremely good material for radiation protection. It’s free real estate ready to be exploited and modified for human use,” said Penny Boston of the New Mexico Institute of Mining and Technology in Socorro. It’s not exactly a leap of the imagination that locations like the Marius Hills skylight could become very valuable regions when space agencies and potential lunar companies need a permanent foothold on the Moon.

A scene from the movie "Moon" with Sam Rockwell

Until we are able to set foot back on the Moon’s surface, we must rely on robotic explorers to do the reconnaissance work (indeed, that is the main priority for NASA’s Lunar Reconnaissance Orbiter, a satellite capable of snapping images 10× sharper than this Kaguya picture), but the fact remains, features like this are very appealing to help protect us humans from the ravages of space.

Bored of the Moon? Set up home in a Martian divot!

Speaking of extraterrestrial housing options, Mars has some trendy sinkholes that might be a little more spacious than your average lunar lava tube

*Technically, it would be a “condo“; anyone living in the lava tube would own the space inside, they wouldn’t own the lava tube itself. We all know that no one can “own” the Moon don’t we? You can throw away that “Congratulations! You’re Now The Proud Owner Of One Acre Of Lunar Real Estate!” certificate, it’s about as valid as those “I Need Your Bank Account Details To Deposit $1 Million” Nigerian royalty emails.

Source: New Scientist. With a special thanks to @foundonmars for the tip!

Moon Water, Confirmed

moon-water

The biggest factor hanging over human settlement of other worlds is the question of water. We need it to drink, we need it to cultivate food, we need it for fuel (indeed, we need it for the first lunar microbrewery); pretty much every human activity requires water. Supplies of water could be ferried from Earth to the Moon, but that would be prohibitively expensive and ultimately futile. For us to live on the Moon or further afield, H2O needs to already be there.

Ever since the Apollo lunar landings when samples of rock were transported to Earth we’ve been searching for the mere hint of this life-giving molecule. There have been indications that the lunar regolith may indeed contain trace amounts of the stuff, but on the whole, scientific endeavour has yet to return evidence of any large supply of water that could sustain a colony.

Until today.

Up until now, scientists haven’t been able to seriously entertain the thought of water on or near the surface of the Moon, apart from in the depths of the darkest impact craters. However, data from the recently deceased Indian Chandrayaan-1 mission has supported data taken by the Cassini probe (when it flew past the Moon in 1999 on its way to Saturn) and NASA’s Deep Impact probe (which made several infrared observations of the lunar surface during Earth-Moon flybys on its way to the 2010 rendezvous with Comet 103P/Hartley 2). Both Cassini and Deep Impact found the signature of water and hydroxyl, and now, a NASA instrument on board Chandrayaan-1 reinforces these earlier findings.

The NASA-built Moon Mineralogy Mapper (M3) on board the Indian satellite detected wavelengths of light reflected off the surface that indicated hydrogen and oxygen molecules. This is convincing evidence that water is either at, or near, the lunar surface. As with the previous measurements, the water signal gets stronger nearer the lunar poles.

So what does this mean for the future of manned space exploration? Although water has been detected, this doesn’t mean there are huge icy lakes for us to pitch a Moon base and pump out the water. In actuality, the signal indicates water, but there is less water than what is found in the sand of the Earth’s deserts (you can pack away the drinking straws now).

It’s still pretty damn dry, drier than anything we have here. But we’ve found this dynamic, ongoing process and the moon was supposedly dead,” University of Maryland senior research scientist Jessica Sunshine told Discovery News. “This is a real paradigm shift.”

If there are widespread water deposits (despite the low concentrations), even in regions constantly bathed in sunlight, there is huge potential for water deposits in those mysterious, frozen craters. Interestingly, these measurements indicate that the water may not have just been deposited there by comets; the interaction between the solar wind and the existing lunar mineralogy could be a mechanism by which lunar ice is constantly being formed.

Every place on the moon, at some point during the lunar day, though not necessarily at all times, has water and OH [hydroxyl],” Sunshine said.

We may see self-sufficient lunar colonies yet. But the saying “getting blood out of a stone” should probably be replaced with “getting water out of the lunar regolith”

Next up is NASA’s LCROSS mission that is scheduled to impact a crater in the south pole on October 9th. Analysis from the impact plume will supplement this positive Chandrayaan-1 result, hopefully revealing yet more water in this frozen region.

Sources: Discovery News, Space.com, Times.co.uk