Far below the surface of the central East Antarctic ice sheet is a body of water 160 miles long by 30 miles across known as Lake Vostok. The Vostok research station above it, for which it was named, was built by the former Soviet Union in 1957 and is now operated by Russia. Even by Antarctic standards, it is a brutal place, with the dubious honor of holding the record for the lowest measured temperature anywhere on the planet, a mind- (if not body-) numbing –129 degrees Fahrenheit (–89 degrees Celsius).

For the past 23 years, with a pause between 1998 and 2004, a hole has been gradually drilled down from this location into the ancient layers of ice. Hints that there could be a vast subsurface body of water arose in the 1950s and 1960s. Ground-penetrating radar later confirmed these suggestions, and Lake Vostok, with its 1,300 cubic miles of liquid water, was revealed some two and a half miles below the ice.

It quickly became clear that this was an environment sealed away from the earth’s surface, and although the water in the lake may itself be slowly changed out by the deep-ice dynamics of Antarctica, this process could take well over 10,000 years. It is also possible that hydrostatic sealing has kept the lake truly isolated for millions of years.

Devoid of light but likely bursting with supersaturated oxygen and other gases, Vostok has long been speculated to be a potential habitat for unique ecosystems of extremophilic microbial life (and who knows what else). Despite the clear risks of contaminating what may be a pristine and fragile environment, Russian scientists have now, eight years after resuming, drilled to the top of the lake. Pressurized water from the lake rose through the borehole and froze, forming a plug. When scientists return this fall, they will remove the plug and check it for signs of life.

It is tremendously exciting, just as it is also tremendously worrying, that we will have messed up yet another irreplace­able ecosystem. If we’re lucky, however, what we will learn about the lost world of Lake Vostok may provide scientific impetus to get ourselves to one of the extraordinary subsurface oceans that exist elsewhere in our solar system, from the Jovian moons Europa and Ganymede to the geyser-spouting mysteries of distant Enceladus. It is possible that what is happening at the Vostok station today is the beginning of our next chapter in the search for life in the universe.

This article was published in print as "Cold Call."