Some lunar oxygen calculations

An article at The Conversation explains how there's a lot of oxygen on the moon - unfortunately, all in the soil and needing a lot of heat to extract.  But still, the maths are interesting:

If we ignore oxygen tied up in the Moon’s deeper hard rock material — and just consider regolith which is easily accessible on the surface — we can come up with some estimates.

Each cubic metre of lunar regolith contains 1.4 tonnes of minerals on average, including about 630 kilograms of oxygen. NASA says humans need to breathe about 800 grams of oxygen a day to survive. So 630kg oxygen would keep a person alive for about two years (or just over).

Only 800g of oxygen a day?  I would have guessed it was more than that, probably influenced by things like the thought of the weight of a full scuba tank!  Of course, there are going to be other gases involved too.  The ISS has a 79% nitrogen atmosphere. 

Anyway, more rough estimates from the article:

Now let’s assume the average depth of regolith on the Moon is about ten metres, and that we can extract all of the oxygen from this. That means the top ten metres of the Moon’s surface would provide enough oxygen to support all eight billion people on Earth for somewhere around 100,000 years.

This would also depend on how effectively we managed to extract and use the oxygen. Regardless, this figure is pretty amazing!

Indeed.