Space scientists have announced a journey to explore the centre of the Moon. Nasa’s $375 million mission will, for the first time ever, unlock the secrets of what lies deep beneath the lunar soil.

But instead of actually digging into the moonrock, Nasa will collect their information using twin satellites which will be put into orbit around the Moon.

They will help Nasa prepare for the return of astronauts to the Moon by 2020 and the establishment of the first manned colonies near one of the lunar poles.

The two spacecraft will work like an X-ray machine, measuring variations in the Moon’s gravity to reveal what lies within from the crust to the core. They will also both carry cameras.

The mission is called GRAIL – the Gravity Recovery and Interior Laboratory – and is due to launch aboard a single rocket in 2011.

Nasa say that, as well as telling us more about the Moon, it will also give scientists a better understanding of how the Earth and other rocky planets in the solar system formed.

Similar techniques have previously been used to probe the Earth’s interior. Nasa science chief Alan Stern said they could one day be used to study Mars and other planets too.

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