The $1 billion mission to reach the Earth's mantle

CNN - Tom Levitt, 10/2/12

• Scientists planning mission to drill down to Earth's mantle and bring back first fresh samples
• Mantle could hold clues to origin and evolution of the planet
• Geologist calls it the most "challenging endeavor in the history of Earth science"
• If project gets the go-ahead, the team hope to reach the mantle by early 2020s

A team of international scientists are planning to drill into the Earth's mantle in an attempt to answer questions about the origins and evolution of life. The drills will need to get through around 6 km of oceanic crust to reach the mantle.

(CNN) -- Humans have reached the moon and are planning to return samples from Mars, but when it comes to exploring the land deep beneath our feet, we have only scratched the surface of our planet.

This may be about to change with a $1 billion mission to drill 6 km (3.7 miles) beneath the seafloor to reach the Earth's mantle -- a 3000 km-thick layer of slowly deforming rock between the crust and the core which makes up the majority of our planet -- and bring back the first ever fresh samples.

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