Discovery Channel will air a two-hour live programme that will reveal what is underneath the 980-feet-wide marine cavern, the Great Blue Hole, 46 miles off the coast of Belize in Central America. The sinkhole, which is over a million years old, has been explored till date only once in 1971 by French explorer Jacques Cousteau. The explorers this time include Jacques Cocteau’s grandson, Fabien Cousteau, Richard Branson and the submersible’s pilot Erika Bergman.

The special, titled Discovery Live: Into The Blue Hole, will be telecast on Discovery at 2.30 am on December 3, with a repeat telecast from 8 pm on Discovery and Discovery HD World.

Though the Great Blue Hole has been explored once, it is yet to be mapped or plotted. This time, once the on-board exploration team of Cousteau, Branson and Bergman are done with the live broadcast, vessels will continue to explore the Great Blue Hole for two weeks and track the area under water, according to a press release. The data collected will help in the construction of real-life models of the sinkhole’s geographical features, which will allow scientists to study the sinkhole’s formation and patterns in climate change.