So American scientists are going to bomb the moon in the hope of finding water.

http://www.independent.co.uk/news/science/scientists-bomb-the-moon-to-search-for-water-1800093.html

I am left somewhat puzzled. Why didn't they notice the water the last time NASA went there? And why is it thought so dangerous now that they have to send unmanned missions when it was fine for Astronauts previously? I never used to give much credence to the conspiracy theorists, but this is all seeming a bit rocky.