NAI

  1. Life Is Left Handed


    The dry, dusty, treeless expanse of Chile’s Atacama Desert is the most lifeless spot on the face of the Earth, and that’s why Alison Skelley and Richard Mathies joined a team of NASA scientists there earlier this month.

    The University of California, Berkeley, scientists knew that if the Mars Organic Analyzer (MOA) they’d built could detect life in that crusty, arid land, then it would have a good chance some day of detecting life on the planet Mars.

    In a place that hadn’t seen a blade of grass or a bug for ages, and contending with ...

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  1. Characterizing the Early Solar Nebula


    A recent Nature paper from Jim Lyons and Ed Young of NAI’s UCLA Lead Team postulates a cause for oxygen isotope anomalies in meteorites that overthrows a long accepted explanation. They propose CO photodissociation due to a far ultraviolet flux caused by a nearby O or B star as a mechanism to produce the isotope fractionation that is consistent with the anomalies observed in the meteorites. The postulated presence of a nearby second star (within one parsec) means statistically that the forming Solar System was probably embedded in a cluster of ~200 stars.

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  1. Linking the Rise in Atmospheric Oxygen With Paleoproterozoic Glaciations


    Andrey Bekker, once with NAI’s former Harvard Lead Team and now part of NAI’s Carnegie Institution of Washington Lead Team, led a study in this month’s Precambrian Research that for the first time documents chemostratigraphy and correlates Early Paleoproterozoic post-glacial carbonates of North America and South Africa.

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  1. Wading in Martian Water


    The European Space Agency’s Mars Express spacecraft has been orbiting Mars for over a year. While the high resolution images of the planet’s many craters, volcanoes, and other features get the most notice, the spacecraft’s seven instruments have also gathered large amounts of data about the planet’s atmosphere, geology, and chemistry. Bernard Foing, ESA Chief Scientist, provides on overview of the most notable discoveries made during Europe’s first trip to the Red Planet.

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  1. Microbial Ecology of Hot Spring Communities in Yellowstone


    New studies from NAI’s University of Colorado team published in the February 15, 2005 issue of PNAS implicate the oxidation of molecular hydrogren as the source of energy for primary productivity in high temperature microbial ecosystems in Yellowstone.

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  1. End of Permian Extinction Theory Draws Technical Comments


    Charles Marshall of NAI’s former Harvard University team published in this week’s Science his commentary on what he calls NAI Principal Investigator Peter Ward’s “groundbreaking” paper from January 2005. The comments are accompanied by a response from Ward et al.

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  1. Could Impacts Have Caused Flooding on Mars?


    NAI scientists on the University of California, Berkeley team describe, in a recent issue of Icarus, how meteoritic impacts on Mars may have caused Earth-like saturated soil liquefaction and potentially enabled violent groundwater eruption. Enough water, they say, could have been erupted to produce floods and outflow channels.

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  1. Increased H2S in the Deep Ocean – Bad News for Life?


    NAI scientists on the Penn State and University of Colorado teams published recently in Geology their studies showing that increases in the level of hydrogen sulfide in the deep ocean during oceanic anoxic periods in Earth’s history could cause elevated H2S levels in shallower waters and in the atmosphere. This may have caused, they propose, destruction of the ozone shield and an increase in atmospheric methane, and may have helped spell the end for life at several extinction events.

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  1. Seeking the Wisdom of the Ancients: Microbial Mats and Biosignatures


    Understanding microbial communities can give clues to how life shaped the Earth billions of years ago – and help find signs of life on distant planets.

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  1. A Mild, Habitable Hadean?


    NAI’s Mark Harrison of the UCLA team co-authored a study published in this week’s Science describing a titanium thermometer technique used to measure the temperature at which ancient zircons from the Jack Hills in Western Australia formed. The results paint a mild picture of the Hadean, complete with an atmosphere and liquid water.

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  1. Teasing Out an Acid Mine Biofilm Microbial Community


    Members of NAI’s UC Berkeley team, led by Jill Banfield, published this week in Sciencexpress their study of the gene expression and protein complement of a microbial biofilm community living in a natural acid mine drainage at Iron Mountain in Northern California. The studies were done on non-cultivated, natural samples, and proteins involved in protein refolding and response to oxidative stress appeared to be highly expressed.

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  1. Uncertain Object Orbiting Brown Dwarf Confirmed as Giant Planet


    NAI’s Ben Zuckerman of the UCLA team told UCLA, “The two objects – the giant planet and the young brown dwarf – are moving together; we have observed them for a year, and the new images essentially confirm our 2004 finding.” The international team recently published their discovery in Astronomy and Astrophysics. Team lead Gael Chauvin of the European Southern Observatory declares this to be the first planet outside our Solar System ever to be imaged.

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  1. The 2005 General Meeting of the NASA Astrobiology Institute


    Many attendees felt that astrobiology had come of age. The NASA Astrobiology Institute (NAI) held its fourth biennial meeting at Boulder, Colorado, April 10-14.

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  1. Iron Record: Ancient Rocks Tell the Story of Oxygen, and Life


    About two billion years ago, a flood of oxygen dramatically changed Earth’s chemistry. Researchers have reconstructed this transformation through studying ancient iron pyrite rocks. Studying the iron in rocks from other planets may give evidence of extraterrestrial life.

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  1. On the Road


    A human geologist could productively cover a two-kilometer stretch of ground in perhaps an hour and a half. For a robotic geologist – NASA’s Spirit rover – it takes a bit longer, more like a month and a half. Still, it’s an impressive journey that will yield important scientific information.

    Spirit’s destination is the Columbia Hills, a group of seven low hills that rise up from the floor of Gusev Crater about 1.7 kilometers (about 1.2 miles) from the rover’s landing site. The Columbia Hills are a tempting target because, scientists believe, they are older than ...

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