Moon living would mean drinking a football pitch every 16 hours
Posted by Jon on Fri 25 Sep 2009Categories: Energy , Environment | [2] Comments
I’ve had a very productive morning. I worked out that, under reasonable conditions, an entire Association Football-approved pitch worth of lunar soil would need to be processed every 16 hours to provide enough water for one person to live relatively comfortably. Water-wise, that is.
The media has happily announced the scientific community’s plans to colonise the Moon, with the recent discovery of significant quantities of water hidden away in Moondust (or whatever it’s called).
A refuelling station, or a full-blown colony for lunar settlers, seems almost within grasp… sort of.
Mark Henderson wrote a great piece in today’s Times titled “Water, water everywhere, but the Moon is still drier than a desert.” I read this as I was putting the finishing touches to my incredibly nerdy spreadsheet, and it verified my own calculations that colonising the Moon is still further away than we’d all hope.
Given that water is contained only within the top few millimetres of soil on the Moon’s surface (source: The Times), that there is a litre or so of water in each metre cubed of soil (source: Science) and that the average colonist would need roughly 4 litres per day to survive in relative comfort (source: a Battlestar Galactica discussion forum), I came up with the following rather arresting stats:
- For each “colonist”, a football pitch’s worth of soil would need to be processed every 16 hours
- This is 12 metric tons of soil
- For a year this is 6510 metric tons, or 545 football pitches
- After this time, at maximum walking speed on the Moon and assuming you worked outwards from your initial location, it would take you 13.4 minutes to walk the two-thirds of a mile to the edge so you could brush your teeth that morning
- It would take 10 million years for that person to use all the water on the Moon
- By this time he would be very lonely and probably not smell very fresh
This is all based on many variables pulled from all over the net, and some I’ve just made up – for example it’s based on 75% extraction efficiency. Who knows if that’s entirely over- or under-estimating what would be realistic?
It also completely ignores other uses for that water, as suggested by the media, such as being electrolysed for use as rocket fuel.
The spreadsheet is on Google Docs so anyone can have a go. Please feel free to fiddle about, and let me know if any of it’s completely wrong or you have better ideas. Any better estimations of the variables would be welcome, but one thing’s for sure: we aren’t going to have self-sustaining colonies up there any time soon.
link to the Google Docs Spreadsheet
