A bizarre microbe found deep in a gold mine in South Africa could provide a model for how life might survive in seemingly uninhabitable environments through the cosmos. Known as Desulforudis audaxviator, the rod-shaped bacterium thrives 2.8 kilometers underground in a habitat devoid of the things that power the vast majority of life on Earth—light, oxygen, and carbon. Instead, this “gold mine bug” gets energy from radioactive uranium in the depths of the mine. Now, scientists predict that life elsewhere in the universe might also feed off of radiation, especially radiation raining down from space. “It really grabbed my attention because it’s completely powered by radioactive substances,” says Dimitra Atri, an astrobiologist and computational physicist who works for the Blue Marble Space Institute of Science in Seattle, Washington. “Who’s to say life on other worlds doesn’t do the same thing?” Essentially all life on Earth's surface takes in the energy it needs through one of two processes. Plants, some bacteria, and certain other organisms collect energy from sunlight through a process called photosynthesis. In it, they use the energy from light to convert water and carbon dioxide into more complex and energetic molecules called hydrocarbons, thus storing the energy so that it can be recovered later by breaking down the molecules through a process called oxidation. Alternatively, animals and other organisms simply feed off of plants, one another, etc., to steal the energy already stored in living things.
Read More: AAAS