There's some carbon on the moon. Rock samples are reported as having on the order of 100 ppm carbon [1]. That means that the amount of carbon in a human body is

There's some carbon on the moon. Rock samples are reported as having on the order of 100 ppm carbon [1]. That means that the amount of carbon in a human body is found in 100 m^3 of lunar soil. So if you extract all the carbon from the top meter of regolith, you could cover the moon with humans on a 10 meter grid spacing. [1] https://www.hq.nasa.gov/alsj/a15/LunarSampleCompendium15265.pdf https://www.hq.nasa.gov/alsj/a15/LunarSampleCompendium15265....