Space probes fly in tandem to search for lunar water - New Scientist
A delicate joint manoeuvre between US and Indian space probes orbiting the moon could turn up evidence for valuable lunar water.
Some scientists suspect water ice – which would be a precious resource for future explorers – may be trapped in permanently shadowed craters at the moon's poles.
Water ice can be distinguished from other materials by the way its radar echoes vary according to the position of the listener. In 1994, the US Clementine spacecraft bounced radar signals off the moon and found hints of the water-ice signature.
It's clear that robotic explorers enable us to do a lot more useful science much more cheaply than human explorers. It's a shame that these robotic explorers are on a mission supporting manned return to moon. What a waste.