For those of you who write SF, this article may spark some ideas. I know I had several flashes in me brain.
Bacteria Found Thriving Deep Underground
A Princeton-led research group has discovered an isolated community of bacteria nearly two miles underground that derives all of its energy from the decay of radioactive rocks rather than from sunlight. According to members of the team, the finding suggests life might exist in similarly extreme conditions even on other worlds.
The self-sustaining bacterial community, which thrives in nutrient-rich groundwater found near a South African gold mine, has been isolated from Earth’s surface for several million years. It represents the first group of microbes known to depend exclusively on geologically produced hydrogen and sulfur compounds for nourishment. The extreme conditions under which the bacteria live bear a resemblance to those of early Earth, potentially offering insights into the nature of organisms that lived long before our planet had an oxygen atmosphere.
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That subterranean world, Onstott said, is a lightless pool of hot, pressurized salt water that stinks of sulfur and noxious gases humans would find unbreathable. But the newly discovered bacteria, which are distantly related to the Firmicutes division of microbes that exist near undersea hydrothermal vents, flourish there.
“The radiation allows for the production of lots of sulfur compounds that these bacteria can use as a high-energy source of food,” Onstott said. “For them, it’s like eating potato chips.”
I’ve got that SF I keep poking on, the one with the sentient planet. I really want the planet itself to be sentient, not some mold, fungus, or bacteria. This article opens up a whole possibility in SF, as well as in the real world.