Assignment 5

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Astrobiology is the field concerned with forming theories, such as panspermia, about the distribution, nature, and future of life in the universe. In it, 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,[1] as many organisms of this type are capable of surviving in environments similar to those known to exist 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 at the subsurface of Antarctica suggests that there may be microbes surviving in endolithic communities and living under Martian surface. Moreover, further researches have suggested that it is unlikely that microbes will live on neither the Martian surface nor at shallow depths, but they may be found at depths around 100 meters below the Martian surface.[note 1]

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 g (i.e. 403,627 times the gravity experienced on Earth). Paracoccus 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 supernovas. Analysis showed that the small size of prokaryotic cells is essential for successful growth under hypergravity. The research has implications on the feasibility of panspermia.[2][3]

On 26 April 2012, scientists reported that lichen survived and showed remarkable results on the adaptation capacity of photosynthetic activity within the simulation time of 34 days under Martian conditions in the Mars Simulation Laboratory (MSL) maintained by the German Aerospace Center (DLR).[4][5]

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".[6]

On 19 May 2014, scientists announced that numerous microbes, like Tersicoccus phoenicis, may be resistant to methods usually used in spacecraft assembly clean rooms. It's not currently known if such resistant microbes could have withstood space travel and are present on the Curiosity rover now on the planet Mars.[7]

On 20 August 2014, scientists confirmed the existence of microorganisms living half a mile below the ice of Antarctica.[8][9]

On September 2015, scientists from CNR-National Research Council of Italy reported that S.soflataricus was able to survive under Martian radiation at a wavelength that was considered extremely lethal to most bacteria. This discovery is significant because it indicates that not only bacterial spores, but also growing cells can be remarkably resistant to strong UV radiation.[note 2]

On June 2016, scientists from Brigham Young University conclusively reported that endospores of Bacillus Subtilis were able to survive high speed impacts up to 299±28 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 spacecrafts 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 speed impact is unknown, and further experiments should be done by introducing higher-velocity impact to bacterial endospores.[note 3]

Notes

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  1. ^ Wynn-Williams, D. A; Newton, E. M.; Edwards, H. G. M (2001). Exo-/astro-biology : proceedings of the first European workshop, 21 - 23 May 2001, ESRIN, Fracscati, Italy. Noordwijk: ESA Publications Div. p. 225. ISBN 92-9092-806-9.
  2. ^ Mastascusa, V.; Romano, I.; Di Donato, P.; Poli, A.; Della Corte, V.; Rotundi, A.; Bussoletti, E.; Quarto, M.; Pugliese, M.; Nicolaus, B. (1 September 2014). "Extremophiles Survival to Simulated Space Conditions: An Astrobiology Model Study". Origins of Life and Evolution of Biospheres. 44 (3): 231–237. doi:10.1007/s11084-014-9397-y. ISSN 0169-6149.
  3. ^ Barney, Brandon L.; Pratt, Sara N.; Austin, Daniel E. (1 June 2016). "Survivability of bare, individual Bacillus subtilis spores to high-velocity surface impact: Implications for microbial transfer through space". Planetary and Space Science. 125 (Supplement C): 20–26. doi:10.1016/j.pss.2016.02.010.

Jiajie Ma (talk) 21:24, 18 November 2017 (UTC)

Assignment 3

edit

Original- "Extremophile"


Astrobiology is the field concerned with forming theories, such as panspermia, about the distribution, nature, and future of life in the universe. In it, 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,[1] 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.[1] The subsurface water ocean of Jupiter's moon Europa may harbor life, especially at hypothesized hydrothermal vents at the ocean floor.

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 g (i.e. 403,627 times the gravity experienced on Earth). Paracoccus 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 supernovas. Analysis showed that the small size of prokaryotic cells is essential for successful growth under hypergravity. The research has implications on the feasibility of panspermia.[10][11]

On 26 April 2012, scientists reported that lichen survived and showed remarkable results on the adaptation capacity of photosynthetic activity within the simulation time of 34 days under Martian conditions in the Mars Simulation Laboratory (MSL) maintained by the German Aerospace Center (DLR).[4][5]

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".[6]

On 19 May 2014, scientists announced that numerous microbes, like Tersicoccus phoenicis, may be resistant to methods usually used in spacecraft assembly clean rooms. It's not currently known if such resistant microbes could have withstood space travel and are present on the Curiosity rover now on the planet Mars.[7]

On 20 August 2014, scientists confirmed the existence of microorganisms living half a mile below the ice of Antarctica.[8][9]

References

edit
  1. ^ a b c Chang, Kenneth (12 September 2016). "Visions of Life on Mars in Earth's Depths". New York Times. Retrieved 12 September 2016.
  2. ^ Than, Ker (25 April 2011). "Bacteria Grow Under 400,000 Times Earth's Gravity". National Geographic- Daily News. National Geographic Society. Retrieved 28 April 2011.
  3. ^ Deguchi, Shigeru; Hirokazu Shimoshige, Mikiko Tsudome, Sada-atsu Mukai, Robert W. Corkery, Susumu Ito, and Koki Horikoshi; Tsudome, M.; Mukai, S.-a.; Corkery, R. W.; Ito, S.; Horikoshi, K. (2011). "Microbial growth at hyperaccelerations up to 403,627 xg". Proceedings of the National Academy of Sciences. 108 (19): 7997–8002. Bibcode:2011PNAS..108.7997D. doi:10.1073/pnas.1018027108. Retrieved 28 April 2011.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. ^ a b Baldwin, Emily (26 April 2012). "Lichen survives harsh Mars environment". Skymania News. Retrieved 27 April 2012.
  5. ^ a b de Vera, J.-P.; Kohler, Ulrich (26 April 2012). "The adaptation potential of extremophiles to Martian surface conditions and its implication for the habitability of Mars" (PDF). European Geosciences Union. Retrieved 27 April 2012.
  6. ^ a b Kim W; Young; Shong; Marchand; Chan; Pangule; Parra; Dordick; Plawsky; Collins; et al. (29 April 2013). "Spaceflight Promotes Biofilm Formation by Pseudomonas aeruginosa". Plos One. 8 (4): e6237. Bibcode:2013PLoSO...862437K. doi:10.1371/journal.pone.0062437. Retrieved 5 July 2013. {{cite journal}}: Explicit use of et al. in: |author2= (help); Unknown parameter |displayauthors= ignored (|display-authors= suggested) (help)CS1 maint: unflagged free DOI (link)
  7. ^ a b Madhusoodanan, Jyoti (19 May 2014). "Microbial stowaways to Mars identified". Nature. doi:10.1038/nature.2014.15249. Retrieved 23 May 2014.
  8. ^ a b Fox, Douglas (20 August 2014). "Lakes under the ice: Antarctica's secret garden". Nature. 512 (7514): 244–246. Bibcode:2014Natur.512..244F. doi:10.1038/512244a. PMID 25143097. Retrieved 21 August 2014.
  9. ^ a b Mack, Eric (20 August 2014). "Life Confirmed Under Antarctic Ice; Is Space Next?". Forbes. Retrieved 21 August 2014.
  10. ^ Than, Ker (25 April 2011). "Bacteria Grow Under 400,000 Times Earth's Gravity". National Geographic- Daily News. National Geographic Society. Retrieved 28 April 2011.
  11. ^ Deguchi, Shigeru; Hirokazu Shimoshige, Mikiko Tsudome, Sada-atsu Mukai, Robert W. Corkery, Susumu Ito, and Koki Horikoshi; Tsudome, M.; Mukai, S.-a.; Corkery, R. W.; Ito, S.; Horikoshi, K. (2011). "Microbial growth at hyperaccelerations up to 403,627 xg". Proceedings of the National Academy of Sciences. 108 (19): 7997–8002. Bibcode:2011PNAS..108.7997D. doi:10.1073/pnas.1018027108. Retrieved 28 April 2011.{{cite journal}}: CS1 maint: multiple names: authors list (link)


Edit- "Extremophile"


Astrobiology is the field concerned with forming theories, such as panspermia, about the distribution, nature, and future of life in the universe. In it, 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,[1] as many organisms of this type are capable of surviving in environments similar to those known to exist 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 maybe microbes such as endolithic communities live under Martian surface.[note 1]

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 g (i.e. 403,627 times the gravity experienced on Earth). Paracoccus 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 supernovas. Analysis showed that the small size of prokaryotic cells is essential for successful growth under hypergravity. The research has implications on the feasibility of panspermia.[2][3]

On 26 April 2012, scientists reported that lichen survived and showed remarkable results on the adaptation capacity of photosynthetic activity within the simulation time of 34 days under Martian conditions in the Mars Simulation Laboratory (MSL) maintained by the German Aerospace Center (DLR).[4][5]

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".[6]

On 19 May 2014, scientists announced that numerous microbes, like Tersicoccus phoenicis, may be resistant to methods usually used in spacecraft assembly clean rooms. It's not currently known if such resistant microbes could have withstood space travel and are present on the Curiosity rover now on the planet Mars.[7]

On 20 August 2014, scientists confirmed the existence of microorganisms living half a mile below the ice of Antarctica.[8][9]

On Jan.09.2015, scientists from CNR-National Research Council of Italy reported that S.soflataricus was able to survive under Martian radiation at a wavelength that was considered extremely lethal to most bacteria. This discovery overturned the dogma that only some bacteria spores were extremely resistant to UV radiation. It also encouraged future researches on S.soflatarcus in space missions to understand what mechanisms this organism uses to survive under extreme conditions.[note 2]

On June 2016, scientists from Brigham Young University reported that endospores of Bacillus Subtilis were able to survive high velocity impacts, extreme shock, and extreme deceleration. They pointed out that this characteristic might allow endospores to survive and be transferred to other locations while experiencing atmosphere disruption or meteorite impact events. Furthermore, they also suggested that a spacecraft might carry spores on its surface, and while it had a hard landing, those spores would impact the landing surface directly and stick on it . Due to their high survivability rate, those spores are likely to survive in a foreign planet.[note 3]

Notes

edit
  1. ^ Wynn-Williams, D. A.; Newton, E. M.; Edwards, H. G. M (2001). Exo-/astro-biology : proceedings of the first European workshop, 21 - 23 May 2001, ESRIN, Fracscati, Italy. Noordwijk: ESA Publications Div. p. 225. ISBN 92-9092-806-9.
  2. ^ Mastascusa, V.; Romano, I.; Di Donato, P.; Poli, A.; Della Corte, V.; Rotundi, A.; Bussoletti, E.; Quarto, M.; Pugliese, M.; Nicolaus, B. (1 September 2014). "Extremophiles Survival to Simulated Space Conditions: An Astrobiology Model Study". Origins of Life and Evolution of Biospheres. 44 (3): 231–237. doi:10.1007/s11084-014-9397-y. ISSN 0169-6149.
  3. ^ Barney, Brandon L.; Pratt, Sara N.; Austin, Daniel E. (1 June 2016). "Survivability of bare, individual Bacillus subtilis spores to high-velocity surface impact: Implications for microbial transfer through space". Planetary and Space Science. 125 (Supplement C): 20–26. doi:10.1016/j.pss.2016.02.010.

Jiajie Ma (talk) 22:55, 8 October 2017 (UTC)

  1. ^ Chang, Kenneth (12 September 2016). "Visions of Life on Mars in Earth's Depths". New York Times. Retrieved 12 September 2016.
  2. ^ Than, Ker (25 April 2011). "Bacteria Grow Under 400,000 Times Earth's Gravity". National Geographic- Daily News. National Geographic Society. Retrieved 28 April 2011.
  3. ^ Deguchi, Shigeru; Hirokazu Shimoshige, Mikiko Tsudome, Sada-atsu Mukai, Robert W. Corkery, Susumu Ito, and Koki Horikoshi; Tsudome, M.; Mukai, S.-a.; Corkery, R. W.; Ito, S.; Horikoshi, K. (2011). "Microbial growth at hyperaccelerations up to 403,627 xg". Proceedings of the National Academy of Sciences. 108 (19): 7997–8002. Bibcode:2011PNAS..108.7997D. doi:10.1073/pnas.1018027108. Retrieved 28 April 2011.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. ^ Baldwin, Emily (26 April 2012). "Lichen survives harsh Mars environment". Skymania News. Retrieved 27 April 2012.
  5. ^ de Vera, J.-P.; Kohler, Ulrich (26 April 2012). "The adaptation potential of extremophiles to Martian surface conditions and its implication for the habitability of Mars" (PDF). European Geosciences Union. Retrieved 27 April 2012.
  6. ^ Kim W; Young; Shong; Marchand; Chan; Pangule; Parra; Dordick; Plawsky; Collins; et al. (29 April 2013). "Spaceflight Promotes Biofilm Formation by Pseudomonas aeruginosa". Plos One. 8 (4): e6237. Bibcode:2013PLoSO...862437K. doi:10.1371/journal.pone.0062437. Retrieved 5 July 2013. {{cite journal}}: Explicit use of et al. in: |author2= (help); Unknown parameter |displayauthors= ignored (|display-authors= suggested) (help)CS1 maint: unflagged free DOI (link)
  7. ^ Madhusoodanan, Jyoti (19 May 2014). "Microbial stowaways to Mars identified". Nature. doi:10.1038/nature.2014.15249. Retrieved 23 May 2014.
  8. ^ Fox, Douglas (20 August 2014). "Lakes under the ice: Antarctica's secret garden". Nature. 512 (7514): 244–246. Bibcode:2014Natur.512..244F. doi:10.1038/512244a. PMID 25143097. Retrieved 21 August 2014.
  9. ^ Mack, Eric (20 August 2014). "Life Confirmed Under Antarctic Ice; Is Space Next?". Forbes. Retrieved 21 August 2014.