Scientists search for life under Antarctic icecap
11 October 2011 Last updated at 07:51 BST
A pioneering British expedition to sample a lake under the Antarctic ice hopes to find unknown forms of life and clues to future climate impacts.
The mission will use hot water to melt its way through ice 3km (2 miles) thick to reach Lake Ellsworth.
The lake has been isolated from the outside world for at least 125,000 years - maybe a million.
Richard Black reports.