1. A Deeper Look Into “Great Dying” Theory

    This week, NAI Principal Investigator Peter Ward published a follow on to his January Science paper which described a potential cause for the extinction events on the P/T boundary: “atmospheric warming because of greenhouse gases triggered by erupting volcanoes.” This new paper, “Hypoxia, Global Warming, and Terrestrial Late Permian Extinctions,” further elucidates this story; its focus is on characterizing environmental degradation approaching and succeeding the “final catastrophe.”

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  1. MISSIONS – Flying a Science Lab to Mars

    Even before the Mars Science Lander (MSL) touches down descending from its hovering mother ship like a baby spider from an egg case the first of a slew of cameras will have started recording, capturing and storing high-resolution video of the landing area.

    The MSL landing will represent a first, says Frank Palluconi, MSL project scientist. After entering the Mars atmosphere- like Viking and MER but with a potential landing zone about one fourth the size – he says, MSL will show its stuff. “It completes the descent down to the ten-meter [33-foot] level, or so, where the descent vehicle hovers ...

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  1. NAI Scientists Turn to Mexican Lake for Clues to Alien Life

    Scientists from NAI’s Virtual Planetary Laboratory recently visited the exotic lakes of Cuatro Ciengas in Mexico’s Chihuahuan desert. What’s being studied there may provide clues what life on other, distant worlds may be like, and help scientists understand and interpret the data coming back from extrasolar planets?

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  1. New Study Implies More Hydrogen in Early Earth Atmosphere Than Previously Thought

    NAI researchers on the University of Colorado Team published a new paper this week in ScienceExpress describing an increased quantity of hydrogen in Earth’s early atmosphere due to a slower escape rate. In contrast to the view that the early atmosphere was oxidizing, this work implies a more favorable “climate” for the production of pre-biotic organic compounds like amino acids, and ultimately, life.

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  1. Eventual Renewal of Frozen Worlds?

    An international collaboration including scientists from NAI’s International Partner, Groupement de Recherche en Exobiologie (GDR Exobio), published recently in Astrophysics their new ideas about the temporal evolution of the circumstellar habitable zone. They describe the possibility of an icy planet in orbit around a star becoming “revived,” and potentially habitable as the star leaves its main sequence. GDR Exobio collaborator Bruno Lopez of the Observatoire de la Cote d’Azur told NASA, “Our result indicates that searches for life-giving worlds outside our Solar System should include planets around old stars.”

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  1. Using Isotopes to Probe the Earliest History of the Solar Nebula

    Members of the NAI UCLA team led by Ed Young are using high-precision analysis of tiny grains in meteorites to probe the earliest history of the solar nebula. The age of the solar system is set at 4.567 billion years, and the new work traces some of the history of these small grains during about 300,000 years, before the formation of comets, asteroids, or planets.

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  1. New Tools to Study Extrasolar Planets

    NAI scientists led one of two teams that have announced the first measurements of light from planets around other stars. The Spitzer Space Telescope detected infrared emissions from these two planets, both of which are “hot Jupiters’ — giant planets orbiting very close to their parent star. This brings a third technique to the study of these planets, which had previously been detected by their gravitational pull on the star and by the dimming of the star as the planet crosses in front of it. As noted by Drake Demming of the Goddard NAI Team, “Spitzer has provided us with a ...

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  1. A Different Type of Marine Thermal Vent

    NAI-supported researchers lead by Deborah S. Kelley of the University of Washington have discovered a new type of marine ecosystem. The Lost City seafloor vents are alkaline rather than acidic, and they produce white chimneys rather than black smokers. Their paper, just published in Science, discusses the unique life found at this locations, such as methane-producing microbes and tiny transparent shrimps and crabs.

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  1. Dry Signs of Life

    A unique rover-based life detection system developed by Carnegie Mellon University scientists has found signs of life in Chile’s Atacama Desert, according to results being presented at the 36th Lunar and Planetary Science Conference March 14-18 in Houston. This marks the first time a rover-based automated technology has been used to identify life in this harsh region, which serves as a test bed for technology that could be deployed in future Mars missions.

    “Our life detection system worked very well, and something like it ultimately may enable robots to look for life on Mars,” said Alan Waggoner, Atacama team ...

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  1. Universe of Disks

    Living next to a ringed planet in a flat solar system in a spiral galaxy may make you think there are a lot of disk-shapes in space. And, indeed, there are. A January 2005 issue of the journal Science contains a special section featuring the roles disks play in the universe.

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  1. NASA Study Suggests Giant Space Clouds Iced Earth

    Astrobiology includes the study of ways that astronomical events can influence the evolution of life on Earth. Alex Pavlov of the NAI University of Colorado team reports in two papers how passage of the solar system through dense cool clouds of dust and gas (called molecular clouds by astronomers) could influence the climate, producing extinctions and perhaps triggering the state known as “snowball Earth”. Much of this research was performed while Pavlov was a NAI postdoctoral fellow.

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  1. Context for the Origin of Life on Earth

    The origins of life – the nature of the transition from inanimate to animate chemistry – is one of the major mysteries of astrobiology. The first of the three theme-questions in astrobiology – Where did we come from? – deals in part with origins, whether the process took place on the ancient Earth or elsewhere. One perspective suggests that chemical interactions between water and various minerals might have been important.

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  1. Touchdown on a Strange Land

    On January 14 the Huygens Probe, built by the European Space Agency, made a soft landing on the surface of Saturn’s moon Titan. The first data from the atmosphere and surface reveal a remarkable place indeed, as described in a science press conference held in Paris on January 21.

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  1. The Greatest Mass Extinction: A Bang or a Whimper?

    At the boundary between the Permian and Triassic periods, 252 million years ago, multi-celled life on planet Earth was nearly terminated. This PT mass extinction represents the greatest dying in the fossil record, with more than 90 percent of species lost. New results from South Africa provide the best-ever picture of the PT extinction on land, suggesting that it was a much more complex process than would be expected for a comet or asteroid impact.

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  1. MISSIONS – Plunge to Methane Lake?

    Imagine descending through hurricane-like conditions where wind speeds can reach 400 miles per hour and the ground temperatures drop as low as -300 degrees Fahrenheit. A choking haze envelopes everything. If all goes well, on January 14, a tiny capsule will take this plunge in hopes of sending back data and pictures near the surface of the Earth-like moon, Titan.

    As part of the Cassini Imaging team studying the atmosphere on Saturn, Anthony Del Genio explained to Astrobiology Magazine his interests in the giant ringed world, Saturn and its strange moons.

    Del Genio is a research scientist at NASA Goddard ...

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