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Earth from Space: Fairbanks, Alaska

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      NASA-supported scientists have examined the long and intricately linked history of microbial life and the Earth’s environment. By reviewing the current state of knowledge across fields like microbiology, molecular biology, and geology, the study looks at how microorganisms have both shaped and been shaped by chemical properties of our planet’s oceans, land, and atmosphere. The study combines data across multiple fields of study and discusses how information on the complicated history of life on our planet from a single field cannot be viewed in isolation.
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      In the new study, the team of researchers provide a review of current knowledge, gleaning information into the early metabolisms used by microbial life, the timing of when these metabolisms evolved, and how these processes are linked to major chemical and physical changes on Earth, such as the oxygenation of the oceans and atmosphere.
      Over time, the prevalence of oxygen on Earth has varied dramatically, in the ocean, in the atmosphere, and on land. These changes impacted both the evolution of the biosphere and the environment. For instance, as the activity of photosynthetic organisms raised oxygen levels in the atmosphere, creating new environments for microbial life to inhabit. Different nutrients were made accessible to life to fuel growth. At the same time, microbes that couldn’t survive in the presence of oxygen had to adapt, perish, or find a way to survive in environments where oxygen didn’t persist, such as deep in the Earth’s subsurface.
      Rocks along the shoreline of Lake Salda in Turkey were formed over time by microbes that trap minerals in the water. These microbialites were once a major form of life on Earth. The new study explains our understanding of how oxygen levels have changed over time and spatial scales. The authors map different types of microbial metabolism, such as photosynthesis, to this history to better understand the “cause-and-effect relationship” between oxygen and the evolution of life on Earth. The paper provides important context for major changes in the course of evolution for the biosphere and the planet.
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      Click here to return to the NASA Astrobiology page.
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    • By NASA
      Official NASA’s SpaceX Crew-9 portraits with Zena Cardman, Nick Hague, Stephanie Wilson and Aleksandr Gorbunov. Credit: NASA Media accreditation now is open for the launch of NASA’s ninth rotational mission of a SpaceX Falcon 9 rocket and Dragon spacecraft that will carry astronauts to the International Space Station for a science expedition. This mission is part of NASA’s Commercial Crew Program.
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      U.S. media, international media without U.S. citizenship, and U.S. citizens representing international media organizations must apply by 11:59 p.m. EDT on Wednesday, July 31. All accreditation requests must be submitted online at:
      NASA’s media accreditation policy is online. For questions about accreditation or special logistical requests, email: ksc-media-accreditat@mail.nasa.gov. Requests for space for satellite trucks, tents, or electrical connections are due by Thursday, Aug. 1.
      For other questions, please contact NASA Kennedy’s newsroom at: 321-867-2468.
      Para obtener información sobre cobertura en español en el Centro Espacial Kennedy o si desea solicitar entrevistas en español, comuníquese con Antonia Jaramillo: 321-501-8425, o Messod Bendayan: 256-930-1371.
      For launch coverage and more information about the mission, visit:
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      Headquarters, Washington
      joshua.a.finch@nasa.gov / claire.a.o’shea@nasa.gov
      Steve Siceloff / Danielle Sempsrott / Stephanie Plucinsky
      Kennedy Space Center, Florida
      steven.p.siceloff@nasa.gov / danielle.c.sempsrott@nasa.gov / stephanie.n.plucinsky@nasa.gov
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