NAI

  1. Timeline of a Mass Extinction


    20111117160954-1.jpg

    Image Credit: Christine Daniloff

    A new study from NASA Astrobiology Program-funded scientists points to rapid collapse of Earth’s species 252 million years ago.

    Since the first organisms appeared on Earth approximately 3.8 billion years ago, life on the planet has had some close calls. In the last 500 million years, Earth has undergone five mass extinctions, including the event 66 million years ago that wiped out the dinosaurs. And while most scientists agree that a giant asteroid was responsible for that extinction, there’s much less consensus on what caused an even more devastating extinction more than 185 ...

    Read More

  1. Sweet Spots for Galactic Organics


    doug\'spaperimage.jpg

    Photo courtesy of NASA.

    Scientists from NAI’s New York Center for Astrobiology at Rensselaer Polytechnic Institute have compiled years of research to help locate areas in outer space that have extreme potential for complex organic molecule formation. The scientists searched for methanol, a key ingredient in the synthesis of organic molecules that could lead to life. Their results have implications for determining the origins of molecules that spark life in the cosmos.

    The findings appear in the Nov. 20 edition of The Astrophysical Journal in a paper titled “Observational constraints on methanol production in interstellar and preplanetary ices.” The ...

    Read More

  1. AbSciCon Call for Abstracts and Conference Registration Opens Nov 22nd


    AbSciConbanner.jpg

    Both the Call for Abstracts and Conference Registration will open on the AbSciCon website on Tuesday, November 22nd. Information on student travel grant applications will also be available, as well as updated logistics information.

    Read More

  1. Cometary Composition in Review


    Astrobiology Program investigators Michael Mumma and Steven Charnley from NASA’s Goddard Space Flight Center have recently published a review entitled The Chemical Composition of Comets: Emerging Taxonomies and Natal Heritage in the Annual Review of Astronomy and Astrophysics. Complimentary, one-time access to the article is provided for your own personal use. Any further/multiple distribution, publication, or commercial usage of this copyrighted material requires submission of a permission request addressed to the Annual Reviews Permissions Department, email permissions@AnnualReviews.org.

    Cometary nuclei contain the least modified material from the formative epoch of our planetary system, and their compositions reflect ...

    Read More

  1. Studying Biology’s Dark Matter


    labchip.jpg

    Polydimethylsiloxane (PDMS) microchip used by the team to sort “dark matter” cells for single-cell genomics. The microchip is mounted on an inverted microscope stage. Credit: Paul Blainey and Steve Quake (Stanford)

    Astrobiologists have long been interested in microorganisms that can survive in the harshest environments that Earth has to offer, from deep sea vents to geothermal hot springs. Unfortunately, these studies are hindered by a phenomenon known as 'biological dark matter.’

    Biological dark matter is a term that refers to the numerous microorganisms that live in natural environments on Earth that cannot be cultivated in a laboratory. In order to ...

    Read More

  1. Follow the Uranium


    endpermian.jpg

    Artist concept of the end-Permian extinction in which 90% of all marine species are thought to have perished. Image Credit: Lunar and Planetary Institute.

    Researchers funded by NASA’s Astrobiology Institute and Exobiology Program have developed a novel geochemical tool that compares the partitioning of uranium isotopes from seawater into carbonates. A decrease of uranium in seawater is indicative of a lack of oxygen (anoxia) in the ocean.

    For the first time ever, this approach has revealed the quantitative levels of dissolved oxygen in ancient oceans at the time of Earth’s largest mass extinction, known as the end-Permian mass ...

    Read More

  1. AbSciCon 2012 Session Topic Submissions


    AbSciConbanner.jpg

    The Call for Session Topics and Session Organizers for AbSciCon 2012 has been extended until OCTOBER 15.

    The Astrobiology Science Conference (AbSciCon) relies on input from the astrobiology community in developing the conference program. The organizing committee is currently seeking nominations for session, symposium and workshop topics. The deadline for session nominations has been extended to October 15, 2011.

    Submit your session topic, visit the conference website at:
    http://abscicon2012.arc.nasa.gov/

    KEY DATES

    September 1, 2011 – Call for Session Topics/Organizers
    October 15, 2011 – SESSION TOPIC PROPOSAL DEADLINE
    November 15, 2011 – Call for Abstracts
    January 31, 2012 – ABSTRACT ...

    Read More

  1. NASA Research Shows DNA Building Blocks Can Be Made in Space


    NASA-funded researchers have found more evidence meteorites can carry DNA components created in space.

    Scientists have detected the building blocks of DNA in meteorites since the 1960s, but were unsure whether they were created in space or resulted from contamination by terrestrial life. The latest research indicates certain nucleobases — the building blocks of our genetic material — reach the Earth on meteorites in greater diversity and quantity than previously thought.

    The discovery adds to a growing body of evidence that the chemistry inside asteroids and comets is capable of making building blocks of essential biological molecules. Previously, scientists found amino acids ...

    Read More

  1. Save the Date: AbSciCon 2012


    abscicon2012-banner.png

    The next Astrobiology Science Conference will be held in Atlanta, GA from April 16—20, 2012. Sign up now to receive conference updates.

    AbSciCon 2012 “Exploring Life: Past and Present, Near and Far” will address our current understanding of life, from processes at the molecular level to those that operate at planetary scales. Studying these aspects of life on Earth provides an essential platform to examine the potential for life within our solar system and beyond.

    AbSciCon 2012 will provide a forum for reporting new discoveries, sharing data and insights, advancing collaborative efforts and initiating new ones, planning new projects ...

    Read More

  1. Searching for Extrasolar Biosignatures


    159626main_art_ultra.jpg

    Researchers supported in part by the NASA Astrobiology Institute and the NASA Exobiology & Evolutionary Biology program have used computer models to study the potential of organic sulfur compounds to be biosignatures in exoplanetary atmospheres. The results indicate that the most detectable feature involves levels of ethane that are higher than expected based on a target planet’s methane concentration. These detection techniques will be particularly useful for finding life on planets similar to the early Earth, that do have life but do not have atmospheric oxygen or ozone, two major biosignature gases. The team suggests that a mission that can detect the ethane and methane in exoplanet atmospheres could find life on such planets, thereby increasing our chances of finding a habitable world outside our solar system.

    The study was recently published in the journal Astrobiology and is now available online. Domagal-Goldman, et ...

    Read More

  1. Arsenic Bacterium Study: Comments and Authors’ Response


    In December of last year, NASA Astrobiology Program Postdoctoral Fellow Felisa Wolfe-Simon and collaborators published a paper online in Science Express describing a bacterium that substitutes arsenic for phosphorus to sustain its growth when in arsenic-rich, phosphorus-depleted medium. Their data showed evidence for arsenate in macromolecules that normally contain phosphate, most notably nucleic acids and proteins. In response to considerable feedback, Science Express has published eight technical comments and a response from Wolfe-Simon and her collaborators. The final version of the original paper will appear in the June 3 print issue of Science. Wolfe-Simon’s research is supported by NASA ...

    Read More

  1. New Evidence Challenges Oldest Signs of Life


    Gallery_Image_7789.jpg

    A photograph of an outcrop of metamorphosed volcanosedimentary rocks from the Porpoise Cove locality, Nuvvuagittuq supracrustal belt, Canada. Image: Mojzsis et. al. / NASA Astrobiology

    Ancient rocks are shedding new light on the timeline for life’s emergence on Earth. The rocks from the Nuvvuagittuq Supracrustal Belt in Quebec, Canada, are believed to be some of the oldest on Earth. They contain carbon-based minerals that had been interpreted as evidence of the Earth’s early biosphere. However, new research funded in part by the NASA Exo/Evo and NAI programs tells a different story. By applying cutting-edge technology to the rocks ...

    Read More

  1. Antarctic Lake Hides Bizarre Ecosystem


    untersee.jpg

    Eerie blue light suffuses the otherworldly bottom of Lake Untersee, Antarctica, where scientists have found structures (purple lumps) built by layer upon layer of growing microbes. Credit: Dale Andersen

    A team of scientists supported by the NASA Exobiology & Evolutionary Biology (Exo/Evo) program have discovered an ecosystem unlike anything previously described deep below the ice of one of the largest and deepest freshwater lakes in East Antarctica. While peering beneath the frozen surface of Lake Untersee, the team identified photosynthetic microbial mats covering the lake’s floor. The mats contain two different microbial communities, each of which produce mats with a distinct morphological structure.

    The Lake Untersee mat structures include stromatolites with a conical morphology that are similar to fossils from the Archean eon (earlier than 2.5 billion years ago). Studying the modern stromatolites in lake Untersee could thereby help scientists understand if ancient stromatolites were ...

    Read More

  1. A Hot, Acidic Primordial Soup


    A new study has revealed that a group of ancient enzymes adapted to substantial changes in ocean temperature and acidity during the last four billion years. The results provide evidence that life on early Earth evolved from an environment that was much hotter and more acidic than today’s. The research was partially funded by the NASA Astrobiology Exo/Evo program and the NASA Astrobiology Institute (NAI). The paper, “Single-molecule paleoenzymology probes the chemistry of resurrected enzymes” was published in the journal Nature Structural & Molecular Biology.

    Source: [Georgia Institute of Technology]

    Read More

  1. Skeletons in the Pre-Cambrian Closet


    CoverPhoto.jpg

    This electron microscope image shows two Pre-Cambrian Cloudina fossils from the Dengying Formation of South China. Credit: S. Xiao

    Researchers are studying some of the earliest skeletons in order to better understand the ancient advancement of animal life. The team is hoping to find out what kind of organisms these Pre-Cambrian organisms were, and whether they left any descendents. The work is being performed with support from the NASA Astrobiology: Exobiology and Evolutionary Biology program.

    Source: [astrobio.net]

    Read More

< prev next >
1 ... 3 4 5 6 7 8 9 10 ... 14