Editing Extremophile (section)

== In astrobiology ==
[[Astrobiology]] is the multidisciplinary field that investigates how life arises, distributes, and evolves in the universe. Astrobiology makes use of [[physics]], [[chemistry]], [[astronomy]], [[solar physics]], [[biology]], [[molecular biology]], [[ecology]], [[planetary science]], [[geography]], and [[geology]] to investigate the possibility of life on other worlds and recognize [[biosphere]]s that might be different from that on Earth.<ref>{{Cite book |title=The life and death of planet Earth |vauthors=Ward PD, Brownlee D |date=2004 |publisher=Owl Books |isbn=978-0805075120 |location=New York}}{{page needed|date=June 2021}}</ref> Astrobiologists are interested in extremophiles, as it allows them to map what is known about the limits of life on Earth to potential extraterrestrial environments<ref name="Rothschild 1092–1101" /> 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 [[Endolith|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.<ref>{{Cite journal|title=The role of habitat structure for biomolecule integrity and microbial survival under extreme environmental stress in Antarctica (and Mars?): ecology and technology|vauthors=Wynn-Williams DA, Newton EM, Edwards HG |date=2001 |journal=Exo-/Astro-biology: Proceedings of the First European Workshop, 21–23 May 2001, ESRIN, Fracscati, Italy  |isbn=978-92-9092-806-5 |volume=496 |page=226 |bibcode=2001ESASP.496..225W}}</ref>

Recent research carried out on extremophiles in [[Japan]] involved a variety of [[bacteria]] including ''[[Escherichia coli]]'' and ''[[Paracoccus denitrificans]]'' being subject to conditions of extreme gravity. The bacteria were cultivated while being rotated in an [[ultracentrifuge]] at high speeds corresponding to 403,627 [[Gravity of Earth|g]] (i.e. 403,627 times the gravity experienced on Earth). ''P.&nbsp;denitrificans'' was one of the bacteria which displayed not only survival but also robust cellular growth under these conditions of hyperacceleration which are usually found only in cosmic environments, such as on very massive stars or in the shock waves of [[supernova]]s. Analysis showed that the small size of [[prokaryotic cell]]s is essential for successful growth under [[hypergravity]]. The research has implications on the feasibility of [[panspermia]].<ref>{{Cite web |last=Than, Ker |date=25 April 2011 |title=Bacteria Grow Under 400,000 Times Earth's Gravity |url=http://news.nationalgeographic.com/news/2011/04/110425-gravity-extreme-bacteria-e-coli-alien-life-space-science/ |archive-url=https://web.archive.org/web/20110427083206/http://news.nationalgeographic.com/news/2011/04/110425-gravity-extreme-bacteria-e-coli-alien-life-space-science/ |url-status=dead |archive-date=27 April 2011 |access-date=28 April 2011 |website=National Geographic – Daily News |publisher=National Geographic Society}}</ref><ref>{{Cite journal |vauthors=Deguchi S, Shimoshige H, Tsudome M, Mukai SA, Corkery RW, Ito S, Horikoshi K |date=May 2011 |title=Microbial growth at hyperaccelerations up to 403,627 x g |journal=Proceedings of the National Academy of Sciences of the United States of America |volume=108 |issue=19 |pages=7997–8002 |bibcode=2011PNAS..108.7997D |doi=10.1073/pnas.1018027108 |pmc=3093466 |pmid=21518884 |doi-access=free}}</ref><ref>{{Cite web |last=Reuell |first=Peter |date=2019-07-08 |title=Harvard study suggests asteroids might play key role in spreading life |url=https://news.harvard.edu/gazette/story/2019/07/harvard-study-suggests-asteroids-might-play-key-role-in-spreading-life/ |access-date=2019-10-06 |website=Harvard Gazette}}</ref>

On 26 April 2012, scientists reported that [[lichen]] survived and showed remarkable results on the [[adaptive capacity|adaptation capacity]] of [[photosynthesis|photosynthetic activity]] within the [[simulation|simulation time]] of 34 days under some [[Life on Mars (planet)#Life under simulated Martian conditions|conditions similar to those on Mars]] in the Mars Simulation Laboratory (MSL) maintained by the [[German Aerospace Center]] (DLR).<ref name="Skymania-20120426">{{Cite web |last=Baldwin |first=Emily |name-list-style=vanc |date=26 April 2012 |title=Lichen survives harsh Mars environment |url=https://www.skymania.com/wp/lichen-survives-harsh-martian-setting/ |access-date=27 April 2012 |publisher=Skymania News |archive-date=12 November 2020 |archive-url=https://web.archive.org/web/20201112042544/https://www.skymania.com/wp/lichen-survives-harsh-martian-setting/ |url-status=dead }}</ref><ref name="EGU-20120426">{{Cite journal |vauthors=De Vera JP, Kohler U |date=26 April 2012 |title=The adaptation potential of extremophiles to Martian surface conditions and its implication for the habitability of Mars |url=http://meetingorganizer.copernicus.org/EGU2012/EGU2012-2113.pdf |journal=EGU General Assembly Conference Abstracts |volume=14 |pages=2113 |bibcode=2012EGUGA..14.2113D |access-date=27 April 2012}}</ref>

On 29 April 2013, scientists at [[Rensselaer Polytechnic Institute]], funded by [[NASA]], reported that, during [[spaceflight]] on the [[International Space Station]], [[microbes]] seem to adapt to the [[space environment]] in ways "not observed on Earth" and in ways that "can lead to increases in growth and [[virulence]]".<ref name="PLos-20130429">{{Cite journal |display-authors=6 |vauthors=Kim W, Tengra FK, Young Z, Shong J, Marchand N, Chan HK, Pangule RC, Parra M, Dordick JS, Plawsky JL, Collins CH |date=29 April 2013 |title=Spaceflight promotes biofilm formation by Pseudomonas aeruginosa |journal=PLOS ONE |volume=8 |issue=4 |pages=e62437 |bibcode=2013PLoSO...862437K |doi=10.1371/journal.pone.0062437 |pmc=3639165 |pmid=23658630 |doi-access=free}}</ref>

On 19 May 2014, scientists announced that some [[microbes]], like ''[[Tersicoccus phoenicis]]'', may be resistant to methods usually used in [[Cleanroom|spacecraft assembly clean rooms]], giving rise to speculation that such microbes could have withstood [[Interplanetary spaceflight|space travel]] and are present on the [[Curiosity (rover)|''Curiosity'' rover]] now on the planet Mars.<ref name="NAT-20140519">{{Cite journal |last=Madhusoodanan |first=Jyoti |name-list-style=vanc |date=19 May 2014 |title=Microbial stowaways to Mars identified |url=https://www.nature.com/news/microbial-stowaways-to-mars-identified-1.15249 |journal=[[Nature (journal)|Nature]] |doi=10.1038/nature.2014.15249 |access-date=23 May 2014 |s2cid=87409424}}</ref>

On 20 August 2014, scientists confirmed the existence of microorganisms living half a mile below the ice of [[Antarctica]].<ref name="NAT-20140820">{{Cite journal |vauthors=Fox D |date=August 2014 |title=Lakes under the ice: Antarctica's secret garden |journal=Nature |volume=512 |issue=7514 |pages=244–46 |bibcode=2014Natur.512..244F |doi=10.1038/512244a |pmid=25143097 |doi-access=free}}</ref><ref name="FRB-20140820">{{Cite web |last=Mack |first=Eric |name-list-style=vanc |date=20 August 2014 |title=Life Confirmed Under Antarctic Ice; Is Space Next? |url=https://www.forbes.com/sites/ericmack/2014/08/20/life-confirmed-under-antarctic-ice-is-space-next/ |access-date=21 August 2014 |website=[[Forbes]]}}</ref>

In September 2015, scientists from [https://www.cnr.it/en CNR-National Research Council] of Italy reported that [[Sulfolobus solfataricus|''S.&nbsp;soflataricus'']] survived under Martian radiation at a wavelength that was considered lethal to most bacteria. This discovery is significant because it indicates that not only bacterial spores, but also growing cells can resist to strong UV radiation.<ref>{{Cite journal |vauthors=Mastascusa V, Romano I, Di Donato P, Poli A, Della Corte V, Rotundi A, Bussoletti E, Quarto M, Pugliese M, Nicolaus B |date=September 2014 |title=Extremophiles survival to simulated space conditions: an astrobiology model study |journal=Origins of Life and Evolution of the Biosphere |volume=44 |issue=3 |pages=231–37 |bibcode=2014OLEB...44..231M |doi=10.1007/s11084-014-9397-y |pmc=4669584 |pmid=25573749}}</ref>

In June 2016, scientists from Brigham Young University reported that [[endospore]]s of ''[[Bacillus subtilis]]'' were able to survive high speed impacts up to 299±28&nbsp;m/s, extreme shock, and extreme deceleration. They pointed out that this feature might allow endospores to survive and to be transferred between planets by traveling within meteorites or by experiencing atmosphere disruption. Moreover, they suggested that the landing of spacecraft may also result in interplanetary spore transfer, given that spores can survive high-velocity impact while ejected from the spacecraft onto the planet surface. This is the first study which reported that bacteria can survive in such high-velocity impact. However, the lethal impact speed is unknown, and further experiments should be done by introducing higher-velocity impact to bacterial endospores.<ref>{{Cite journal |vauthors=Barney BL, Pratt SN, Austin DE |date=June 2016 |title=Survivability of bare, individual Bacillus subtilis spores to high-velocity surface impact: Implications for microbial transfer through space |journal=Planetary and Space Science |volume=125 |pages=20–26 |bibcode=2016P&SS..125...20B |doi=10.1016/j.pss.2016.02.010}}</ref>

In August 2020 scientists reported that bacteria that [[Microbial metabolism|feed on]] air discovered 2017 [[Antarctic microorganism#Bacteria|in Antarctica]] are likely not limited to Antarctica after discovering the two genes previously linked to their "atmospheric chemosynthesis" in soil of two other similar cold desert sites, which provides further information on this [[carbon sink]] and further strengthens the extremophile evidence that supports the potential existence of microbial life on alien planets.<ref>{{Cite news |title=Microbes living on air a global phenomenon |language=en |work=phys.org |url=https://phys.org/news/2020-08-microbes-air-global-phenomenon.html |access-date=8 September 2020}}</ref><ref>{{Cite news |date=19 August 2020 |title=Bacteria that "eat" only air found in cold deserts around the world |work=New Atlas |url=https://newatlas.com/biology/air-eating-bacteria-antarctica-artic/ |access-date=8 September 2020}}</ref><ref>{{Cite journal |last1=Ray |first1=Angelique E. |last2=Zhang |first2=Eden |last3=Terauds |first3=Aleks |last4=Ji |first4=Mukan |last5=Kong |first5=Weidong |last6=Ferrari |first6=Belinda C. |date=2020 |title=Soil Microbiomes With the Genetic Capacity for Atmospheric Chemosynthesis Are Widespread Across the Poles and Are Associated With Moisture, Carbon, and Nitrogen Limitation |journal=Frontiers in Microbiology |language=en |volume=11 |page=1936 |doi=10.3389/fmicb.2020.01936 |issn=1664-302X |pmc=7437527 |pmid=32903524 |doi-access=free |s2cid=221105556}} [[File:CC-BY icon.svg|50px]]  Text and images are available under a [https://creativecommons.org/licenses/by/4.0/  Creative Commons Attribution 4.0 International License].</ref>

The same month, scientists reported that bacteria from Earth, particularly ''[[Deinococcus radiodurans]]'', were found to survive for three years in [[outer space]], based on studies on the [[International Space Station]]. These findings support the notion of [[panspermia]].<ref name="CNN-20200826">{{Cite news |last=Strickland |first=Ashley |date=26 August 2020 |title=Bacteria from Earth can survive in space and could endure the trip to Mars, according to new study |work=[[CNN News]] |url=https://www.cnn.com/2020/08/26/world/earth-mars-bacteria-space-scn/index.html |access-date=26 August 2020}}</ref><ref name="FM-20200826">{{Cite journal |last=Kawaguchi, Yuko |display-authors=et al. |date=26 August 2020 |title=DNA Damage and Survival Time Course of Deinococcal Cell Pellets During 3 Years of Exposure to Outer Space |journal=[[Frontiers in Microbiology]] |volume=11 |page=2050 |doi=10.3389/fmicb.2020.02050 |pmc=7479814 |pmid=32983036 |doi-access=free |s2cid=221300151}} [[File:CC-BY icon.svg|50px]]  Text and images are available under a [https://creativecommons.org/licenses/by/4.0/  Creative Commons Attribution 4.0 International License].</ref>