Extremophile

An extremophile is an organism, almost always microbial, that thrives in physical or chemical conditions once thought too extreme to support life, including extreme heat, cold, acidity, alkalinity, pressure, salinity or radiation. Examples include thermophiles found in boiling hydrothermal vents, psychrophiles that grow in permanently frozen environments, and organisms recovered from highly acidic mine drainage or the cores of nuclear reactors. Their existence has substantially broadened scientific estimates of where life might survive elsewhere in the solar system, including in the subsurface oceans of icy moons such as Europa and Enceladus, and informs the design of missions searching for extraterrestrial life.