Horizon Season 50 Episode 4 -

Airdate: 2011-Aug-31

Episode summary:

For many centuries humans have dreamt of reaching the centre of the Earth. Scientists are bow uncovering a strange and alien world that lies 4,000 miles beneath the ground.

About Horizon series:

Series exploring topical scientific issues and their effects for the future. Horizon is the BBC2 documentary that explores and educates us about co...Show more >