Final checks are under way in Antarctica before the launch of a daring attempt to investigate an ancient lake beneath the ice-sheet.
Lake Ellsworth lies below ice that is at least two miles (3.2km) thick.
Its pitch-black waters have remained isolated and unseen for up to half a million years.
This will be the first attempt to extract uncontaminated samples of water and sediment from a body of water so far below the surface.
The investigation is part of a search to understand the limits of where life is possible and, despite the high pressures and lack of sunlight, it is likely that microbes will be detected.
The lake is about 14km long, 3km wide and 160m deep - about the size of Lake Windermere, England's largest.
In a region of Antarctica notorious for its low temperatures and near-constant winds, operating at this location is a huge challenge.
The project is made all the tougher because of the need for all the equipment to be kept sterile throughout the process ( via bbc.co.uk ).
Now the experiment is set we can hit the Go button.”