In 2009, NASA sent a satellite to the Moon to map it in detail. It was called the Lunar Reconnaisance Orbiter (LRO). But they added another satellite called the sheparding craft that remained attached to the Centaur upper stage. After the LRO separated, the sheparding craft steered the Centaur upper stage towards a particular, permanently-shadowed crater at the lunar south pole called Cabeus Crater. The sheparding craft separated and spectroscopically imaged the icy dirt kicked up into the sunlight when the Centaur crashed into Cabaeus Crater. These cubes illustrate what they found.

They found that for each square meter of icy dirt, one part per 18 (by mass) was water ice. Since the denisty of water is less than the density of the dirt, the volume of the water here appears even greater. But it wasn't just water that they found. They also found organic chemicals that one would normally expect to see in comets. This included some very useful chemicals such as a substantial amount of ammonia which contains nitrogen of use for fertilizer and breathable air. It also contains ethylene which, once polymerized, can make plastic.

Operations producing propellant-quantities of water would yield a large amount or organic chemicals. A base with a million settlers that recycles well, the estimated water would last for 1,600 years. And during that time, asteroid and cometary sources could be developed and delivered to the Moon. In short, a lunar settlement will never run out of the necessary resources that it needs.

Now, what we need is a way of converting Martian air into breathable air. How could we do that? For starters, we need to filter out the nitrogen and argon in order to make up 80% of our breathable air. Then, how do we get the very important O2? Well, there’s really not enough free O2 in the Martian air. So, we could electrolyze water – that’s one way. Or we could electrolyze CO2 – there’s plenty of O2 there. Finally, we can use plants to convert the CO2 into O2. So there’s several different solutions there.

On a very large scale, we have a poster showing how we could create ever-increasing greenhouses and process the Martian atmosphere to create breathable air. It is a process we call paraterraforming. Now, some greenhouses could be pure CO2 which plants can happily grow in. Using this approach, we could even establish greenhouses across the entire surface of Mars as a very rapid alternative to the terraformation of Mars.

When we compare these regolith simulants of the Moon and Mars, immediately we see the color difference. Lunar regolith is basically powdered rock while Mars is largely oxidized iron otherwise known as rust.

The dirt on the Moon was created differently than that on Mars and so the two are quite unlike each other. On the Moon, the dirt has been created by eons of impact events from huge asteroid impacts to frequent micrometeorite impacts. The energy of impacts turns the regolith into glass. Later impacts break down that glass into extremely fine particles. These particles have been likened to cigarette smoke. The particles are so fine that they leave a perfect impression when stepped on.

But they are still fractured pieces of glass and hence very fine and abrasive. For this reason, they are terrible for precision joints in equipment and for textured space suits and outer habitat layers. Also, if you inhale the stuff it really irritates the respiratory passages – not good.

Now, Martian regolith has its own problems. Whereas wind on Mars has smoothed out the dust, the oxidative environment on Mars none-the-less creates some hazardous chemicals, namely, perchlorates. This is an oxidant in solid rocket fuel. Ingest that and you end up damaging your thyroid.

Yes, studies show that you can grow plants in the regolith of the Moon and Mars if you treat it correctly. But having gardeners working around the stuff inside GreenHabs doesn’t sound like the best idea to us. Instead, the Network’s Agriculture Working Group has considered the situation and we believe it best to leave dust outside of the habs as much as possible. To this end, we believe that any soil in the GreenHabs should come from washed rocks that we crush down to size and then built up into soil using plant refuse, bacteria, and fungi.

Our Network has identified a set strategies to avoid the effects of dust in all the various circumstances. That can be found at: DevelopSpace.info/dust