An extremophile is an organism with optimal growth in environmental conditions considered extreme in comparison to the environmental conditions that are comfortable to humans. In contrast, organisms that live in more moderate environmental conditions, according to an anthropocentric view, may be termed mesophiles or neutrophiles. In the 1980s and 1990s, biologists found that microbial life has great flexibility for surviving in extreme environments—niches that are acidic or extraordinarily hot, for example—that would be inhospitable to complex organisms; some scientists concluded that life may have begun on Earth in hydrothermal vents far under the ocean's surface. According to astrophysicist Steinn Sigurdsson, "There are viable bacterial spores that have been found that are 40 million years old on Earth—and we know they're hardened to radiation." Some bacteria were found living in the cold and dark in a lake buried a half-mile deep under the ice in Antarctica, in the Marianas Trench, the deepest place in Earth's oceans.

Some microorganisms have been found thriving inside rocks up to 1,900 feet below the sea floor under 8,500 feet of ocean off the coast of the northwestern United States. According to one of the researchers, "You can find microbes everywhere—they're adaptable to conditions, survive wherever they are." A key to extremophile adaptation is their amino acid composition, affecting their protein folding ability under particular conditions.. Studying extreme environments on Earth can help researchers understand the limits of habitability on other worlds. Tom Gheysens from Ghent University in Belgium and some of his colleagues have presented research findings that show spores from a species of Bacillus bacteria survived and were still viable after being heated to temperatures of 420 °C. There are many classes of extremophiles; these classifications are not exclusive. Many extremophiles are classified as polyextremophiles. For example, organisms living inside hot rocks deep under Earth's surface are thermophilic and barophilic such as Thermococcus barophilus.

A polyextremophile living at the summit of a mountain in the Atacama Desert might be a radioresistant xerophile, a psychrophile, an oligotroph. Polyextremophiles are well known for their ability to tolerate both low pH levels. Acidophile An organism with optimal growth at pH levels of 3.0 or belowAlkaliphile An organism with optimal growth at pH levels of 9.0 or aboveAnaerobe An organism with optimal growth in the absence of molecular oxygen. Two sub-types exist: facultative obligate anaerobe. A facultative anaerobe can tolerate anoxic and oxic conditions whilst an obligate anaerobe will die in the presence of low levels of molecular oxygen. Cryptoendolith An organism that lives in microscopic spaces within rocks, such as pores between aggregate grains; these may be called endolith, a term that includes organisms populating fissures and faults filled with groundwater in the deep subsurface. Halophile An organism with optimal growth at a concentration of dissolved salts of 50 g/L or above. Hyperpiezophile An organism with optimal growth at hydrostatic pressures above 50 MPa.

Hyperthermophile An organism with optimal growth at temperatures above 80 °C. Hypolith An organism that lives underneath rocks in cold deserts. Metallotolerant Capable of tolerating high levels of dissolved heavy metals in solution, such as copper, cadmium and zinc. Examples include Ferroplasma sp. Cupriavidus metallidurans and GFAJ-1. Oligotroph An organism with optimal growth in nutritionally limited environments. Osmophile An organism with optimal growth in environments with a high sugar concentration. Piezophile An organism with optimal growth in hydrostatic pressures above 10 MPa. Referred to as barophile. Polyextremophile A polyextremophile is an organism that qualifies as an extremophile under more than one category. Psychrophile/Cryophile An organism with optimal growth at temperatures of 15 °C or lower. Radioresistant Organisms resistant to high levels of ionizing radiation, most ultraviolet radiation; this category includes organisms capable of resisting nuclear radiation. Thermophile An organism with optimal growth at temperatures above 45 °C.

Xerophile An organism with optimal growth at water activity below 0.8. Astrobiology is the study of the origin, evolution and future of life in the universe: extraterrestrial life and life on Earth. Astrobiology makes use of physics, astronomy, solar physics, molecular biology, planetary science and geology to investigate the possibility of life on other worlds and help recognize biospheres that might be different from that on Earth. Astrobiologists are interested in studying extremophiles, as their habitats may be analogous to conditions on other planets. For example, analogous deserts of Antarctica are exposed to harmful UV radiation, low temperature, high salt concentration and low mineral concentration; these conditions are similar to those on Mars. Therefore, finding viable microbes in the subsurface of Antarctica suggests that there may be microbes surviving in endolithic communities and living under the Martian surface. Research indicates it is unlikely that Martian microbes exist on the surface or at shallow depths, but may be found at subsurface depths of around 100 meters.

Recent research carried out on extremophiles in Jap

Wilfred White (ice hockey)

Wilfred Belmont "Tex" White was a Canadian professional ice hockey forward who played seven seasons in the National Hockey League for the Pittsburgh Pirates, New York Americans and Philadelphia Quakers. While White was addressed in numerous newspaper articles as "Tex", no explanation was given as to how he got that nickname. From 1917 to 1923, played with the Barrie Canoe Club, Toronto Canoe Club, Dunville Dunnies of the Ontario Hockey Association. In 1923, after seeing how well the fans in Pittsburgh took to Lionel Conacher, the owner of the Pittsburgh Yellow Jackets, Roy Schooley, asked Conochar to invite a number of his friends in Canada to play for his team; these players included Harold Cotton, Hib Milks, Harold Darragh, Rodger Smith, Duke McCurry, Roy Worters and "Tex" White. White played for the Yellow Jackets for the next two seasons, helping the team win the United States Amateur Hockey Association title in each of those years. In 1925, the Yellow Jackets morphed into the NHL's Pittsburgh's Pirates.

Tex made the transition to the NHL with several other key members of the team. White was one of only five Pittsburgh players to play all five seasons for the Pirates; however he played for the New York Americans for 13 games at the end of the 1928-29 NHL season, sent to the New Haven Eagles, of the Canadian-American Hockey League, for 12 games in 1929-30. When financial issues associated with the Great Depression sent the Pirates across the state to Philadelphia, White stayed with the team, now renamed the Philadelphia Quakers, he scored three goals in his one month playing for the Quakers, with one of those goals being the game winner in the Quakers' first victory, over the Toronto Maple Leafs on November 25, 1930. However Tex was traded, along with Rodger Smith, to the revived Pittsburgh Yellow Jackets for cash on December 16, 1930, following the Quakers' acquisition of Eddie McCalmon and D'Arcy Coulson. On March 17, 1931, White scored the lone goal for the Yellow Jackets against the London Tecumsehs.

The win allowed Pittsburgh to clinch a playoff berth in the International Hockey League. He played in Pittsburgh before retiring from hockey in 1932, he was found dead in his Canadian Corps Club room, located in Port Colborne, Ontario, on December 2, 1948. He had been working as a steward for the previous three years. Biographical information and career statistics from, or, or, or The Internet Hockey Database

Mirage Celerity

The Mirage Celerity is an American two-seat cabin monoplane designed by Larry Burton and with plans for home building sold by Mirage Aircraft of Tucson AZ, United States. The Celerity is a side-by-side two-seat low-wing cabin monoplane built from a mixture of composites and wood. Nominally powered by a 160 hp Lycoming O-320-B1A piston engine and with a retractable conventional landing gear. In September 2014 three examples were registered in the United States with the Federal Aviation Administration, although a total of four had been registered at one time. Data from Brassey's World Aircraft & Systems DirectoryGeneral characteristics Crew: 2 Length: 21 ft 6 in Wingspan: 23 ft 10 in Empty weight: 1169 lb Gross weight: 1825 lb Powerplant: 1 × Lycoming O-320-B1A, 160 hp Performance Maximum speed: 220 mph Stall speed: 53 mph Range: 1000 miles Rate of climb: 1800 ft/min Official website