A study undertaken recently seems to have had its 'eureka' moment with urea, which is also found in human urine!
We have all been hearing of bases on the Moon and Mars, but the problem seems to have been construction material to build the same. It was too much to cart so much of material into space so the focus was on using locally found materials on those planets.
To quote
Since transportation to the Moon can cost up to USD 10,000 for 0.45 kgs, the researchers are planning on ways to construct the bases with raw material available on the planet itself and the ones provided by the astronauts themselves - their urine.
Urea, from astronauts urine, was found to be a great plasticizer, an additive which can be mixed in concrete to make it pliable till it hardens.
As per the study, if we are ever have to have a base on the moon, it will be made of lunar soil mixed with water and human urine!
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