Establishing lunar colonies seems like the next logical step, it’s our closest celestial body after all, however it might surprise you to learn that doing that might in fact be a lot harder than establishing a similarly sized colony on Venus or Mars. Without an atmosphere to speak of our Moon’s surface is an incredibly harsh place with the full brunt of our sun’s radiation bearing down on it. That’s only half the problem too as since the day/night cycles last 2 weeks you’ll spend half your time in perpetual darkness at temperatures fast approaching absolute zero. There are ways around it however and recent research has led to some rather interesting prospects.
Whilst the surface of the Moon might be unforgiving going just a little bit below the surface negates many of the more undesirable aspects. Drilling into the surface is one option however that’s incredibly resource intensive, especially when you consider that all the gear required to do said drilling would need to be sent from Earth. The alternative is to use structures that are already present on the Moon such as caverns and other natural structures. We know that these kinds of formations are already present on the Moon thanks to the high resolution imagery and gravity mapping we’ve done (the Moon’s gravity field is surprisingly non-uniform) but just how big these structures could be has remained somewhat of a mystery.
Researchers at Purdue university decided to investigate just how big structures like these could be, specifically looking at how big lava tubes could get if they existed on the Moon. During its formation, which would have happened when a large object collided with the then primordial Earth, the surface of the Moon would have been ablaze with volcanic activity. However due to its much smaller size that activity has long since ceased but it would have still left behind the tell tale structures of its more tumultuous history. The researchers then modelled how big these tubes could have gotten given the conditions present on the Moon and came up with a rather intriguing discovery: they’d be huge.
When you see the outcome of the research it feels like an obvious conclusion, of course they’d be bigger since there’s less gravity, but the fact that they’re an order of magnitude bigger than what we’d see on Earth is pretty astounding. The picture above gives you some sense of scale for these potential structures, able to fit several entire cities within them with an incredible amount of room to spare. Whilst using such structures as a basis for a future lunar colony presents a whole host of challenges it does open up the possibility to the Moon having much more usable space than we first thought.