Researchers have discovered an isolated, self-sustaining bacterial community living under extreme conditions almost two miles deep beneath the surface in a South African gold mine. It is the first microbial community demonstrated to be exclusively dependent on geologically produced sulfur and hydrogen and one of the few ecosystems found on Earth that does not depend on energy from the Sun in any way. The bacteria live in ancient water trapped in a crack in basalt rock, 3 to 4 kilometres down, by harvesting the energy of natural radioactivity to create food for themselves. The discovery, appearing in the October 20 issue of „Science“, raises the possibility that similar bacteria could live beneath the surface of other worlds, such as Mars or Jupiter’s moon Europa.

Otherworldly Bacteria Discovered Two Miles Down