Scientists who blasted a spent rocket into a lunar crater last year released an unexpected treasure trove of elements -- including traces of silver.
But the levels are far too low to make it worth opening a lunar silver mine.
More importantly for space exploration, large amounts of water were discovered at the bottom of the Cabeus crater.
Making up around 5.6pc of the surface material, it was present in sufficient quantities to be useful to future manned missions. Less welcome was the detection of high levels of mercury in the soil, posing a potential risk to explorers.
The findings, reported in the journal 'Science', showed that the crater soil was far more complex than expected. Not only did it contain water, but a plethora of other compounds and elements including mercury, calcium, magnesium, carbon monoxide and dioxide, ammonia and sodium.