# Why can't we prepare the moon for colonization by shipping oxygen to its atmosphere?

Why can't we take oxygen to the moon in order to civilize it? We can store oxygen in rockets then take them to moon and release it there. Even if the moon's gravity is weak, it will hold on to the oxygen.

• Take a look at this image. An entire Saturn V rocket would be ~1/15th of a pixel long. I think that answers your question. – Kris Walker Oct 14 '17 at 7:33
• have a look at the answer here for some thing attainable forbes.com/sites/quora/2016/05/25/… – anna v Dec 24 '17 at 13:25

The main problem is that it would be a lot of oxygen. Just a ten-foot layer of one atmosphere air (pretending you could somehow get it to stay in a ten-foot layer) over the moon would weigh around $10^{14} \rm kg$. It costs around \$20,000 per kilogram to send something into low earth orbit, and much more for the moon (more than a million dollars probably). So it would cost around \$$10^{20} dollars, or the world's GDP for about one million years. And to actually give a one atmosphere surface pressure would almost certainly require much more oxygen. If you didn't magically keep all the atmosphere in 10 feet, the total mass you would need is$$\frac{4\pi r^2 P_{m}}{g_{m}}\approx 2\cdot 10^{18}\rm kg$$which obviously makes it a lot worse. Plus, as J.G. mentioned, that would be a pretty noticeable fraction of the earth's atmosphere at that point. And even if you managed it, the air would only stick around for maybe 1000 years. Doesn't quite seem worth it, does it? • In fact to get 1 atm we'd need to send up a big chunk of Earth's oxygen, so even if the transport could be made cheap we'd either have to free oxygen from a lot of some compound or let Earth's atmospheric oxygen plummet, which is a bad idea too. – J.G. Oct 14 '17 at 8:04 • @J.G. Yeah, that too ;) – Chris Oct 14 '17 at 8:10 • There may be ice at the poles of the Moon. Use solar cells to produce electricity and then electrolysis to split the water. – badjohn Oct 14 '17 at 9:09 • @badjohn Sure, if there's ice at the poles of the moon and, critically, if there's enough ice at the poles of the moon. But you run into some minor power issues: since you need around$10^{18}\rm kg\$ of air, though, that's going to take around 10 yottajoules of energy. Which would take the entire world's power supply more than 100,000 years to provide. Needless to say, solar cells aren't going to cut it ;) Edit: Come to think of it, that's ignoring the energy it takes just to melt the ice so you can start electrolysis. So it's even worse! – Chris Oct 14 '17 at 9:13