The exploration of the Moon is maybe best compared with the expeditions to Antarctica. They are both uncompromising, extreme environments that, at first, would appear to have little to offer to human advancement. As it's turned out, Antarctica has proved to be vital for scientific discovery. It has taught us about our atmosphere, oceans and climate. 18th and 19th century explorers were desperate to discover that last continent - in the 21st century the Moon provides an even greater challenge.

Many of these missions, including MoonLite, are far from assured. And there is no shortage of people suggesting we're better spending money elsewhere. But who can fail to be inspired when they look up at the Moon on a clear night? Perhaps the most important thing about this anniversary is not that we've been to the Moon, it's that we're now going back.