Want to stay on top of all the space news? Follow @universetoday on TwitterExtremophiles are organisms that thrive in, and may require, physically, or geo-chemically extreme conditions to live. These conditions are always detrimental to the majority of life on Earth.
In the 1980s and 1990s, biologists found that microbial life has an amazing flexibility for surviving in extreme environments. Some of this life survive in niches that are extraordinarily hot, or cold, or dry, or under immense pressures. Some scientists even concluded that life may have begun on Earth in hydrothermal vents far under the ocean’s surface. Most known extremophiles are microbes. The Archaea family contains several well known examples, but they are present in numerous and diverse types of both bacteria and archaeans. These are not limited to single cell life-forms. Multi-cell varieties include the Pompeii worm, Antarctic krill, and the water bear(microscopic, water-dwelling, segmented animals with eight legs). This type of creature has been found in acidic, salty, alkaline, high temperatures, low temperatures, living inside rocks, etc. There seems to be no environment on Earth that does not have some kind of microbe or animal surviving in it.
This leads us to the study of astrobiology(life in space). In this field of study, microbial ecologists, astronomers, planetary scientists, geochemists, philosophers, and explorers cooperate constructively to guide the search for life on other planets. Astrobiologists are particularly interested in studying extremophiles, as many organisms of this type are capable of surviving in environments similar to those known to exist on other planets. For example, Mars may have regions in its deep subsurface permafrost that could harbor endolith communities. The subsurface water ocean of Jupiter’s moon Europa may harbor life, especially at hypothesized hydrothermal vents at the ocean floor. If microbes can survive where science thought it impossible here on Earth, why not else where in the solar system and universe?
Here is an article about the types of extremophiles here on Earth. We have a great article about life on Mars here on Universe Today. Astronomy Cast offers a good episode about astrobiology and its implications.