After 20 years, Russian scientists have drilled into the never-before-touched Lake Vostok 2.2 miles below the surface of Antarctica, a Russian news agency reported Monday. The underground lake, a body of water that wasn't discovered until the mid-1990s, is the world's third-largest by volume. It hasn't been exposed to surface air for 20 million years and could contain new lifeforms, though there are concerns the drilling materials and bacteria could contaminate it.
