This old planet has almost - but not quite - run out of unexplored corners. Humankind has been just about everywhere (and we've left behind the rubbish to prove it).
So it is exciting, but also a little saddening, that one of the last unknown bits of the Earth has now been opened up.
Under the ageless Antarctic ice, geothermal heat has created hundreds of lakes; some have been isolated for thousands, perhaps millions, of years. Now Russian scientists have for the first time drilled down into one of the biggest of these reservoirs, Lake Vostok, which stretches across 15,000 square km beneath the East Antarctic Ice Sheet, home of the coldest natural temperature ever recorded, -89C.
The Russians say they hope to find microbial life forms which have endured or evolved without sunlight or fresh air, and which could provide new evidence to test a range of biological theories.
Readers who remember the 1982 horror movie The Thing, about scientists rousing a monster from under the Arctic ice, may be a little wary of the Russian project. But the urge to explore is a basic element of human nature, and scientific investigation has provided incalculable benefits to us all. This is no time to stop. We just hope the Russians - and the other governments drilling holes on the White Continent - don't leave a mess of plastic bags and McDonald's wrappers behind.