SETI public: Fw: Los Alamos Release New Maps Of Mars Water

Date: Wed Jul 30 2003 - 09:06:53 PDT

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    ----- Original Message -----
    From: Ron Baalke - Mars Exploration Program
    Sent: Friday, July 25, 2003 12:48 PM
    Subject: Los Alamos Release New Maps Of Mars Water

    Los Alamos releases new maps of Mars water

    Contact: Nancy Ambrosiano,, (505) 667-0471 (03-101)

    Contact: Jim Danneskiold,, (505) 667-1640

    July 24, 2003

    LOS ALAMOS, N.M. -- "Breathtaking" new
    maps of likely sites of water on Mars showcase their
    association with geologic features such as Vallis Marineris,
    the largest canyon in the solar system.

    The maps detail the distribution of water-equivalent
    hydrogen as revealed by Los Alamos National
    Laboratory-developed instruments aboard NASA's Mars
    Odyssey spacecraft. In an upcoming talk at the Sixth
    International Conference on Mars at the California Institute of
    Technology, in Pasadena, Los Alamos space scientist Bill
    Feldman and coworkers will offer current estimates of the
    total amount of water stored near the Martian surface. His
    presentation will be at 1:20 p.m., Friday, July 25.

    For more than a year, Los Alamos' neutron spectrometer has
    been carefully mapping the hydrogen content of the planet's
    surface by measuring changes in neutrons given off by soil, an
    indicator of hydrogen likely in the form of water-ice. The new
    color maps are available at


    "The new pictures are just breathtaking, the
    water-equivalent hydrogen follows the geographic features
    beautifully," said Feldman. "There's a lane of hydrogen-rich
    material following the western slopes of the biggest
    volcanoes in the solar system, a maximum reading sits right
    on Elysium mons, and another maximum is in the deepest
    canyon in the solar system."

    The new maps combine images from the Mars Orbiter Laser
    Altimeter (MOLA) on the Mars Global Surveyor with Mars
    Odyssey spectrometer data through more than half a Martian
    year of 687 Earth days. From about 55 degrees latitude to the
    poles, Mars boasts extensive deposits of soils that are rich in
    water-ice, bearing an average of 50 percent water by mass.
    In other words, Feldman said, a typical pound of soil scooped
    up in those polar regions would yield an average of half a
    pound of water if it were heated in an oven.

    The tell-tale traces of hydrogen, and therefore the presence
    of hydrated minerals, also are found in lower concentrations
    closer to Mars' equator, ranging from two to 10 percent water
    by mass. Surprisingly, two large areas, one within Arabia
    Terra, the 1,900-mile-wide Martian desert, and another on
    the opposite side of the planet, show indications of relatively
    large concentrations of sub-surface hydrogen.

    Scientists are attracted to two possible theories of how all
    that water got into the Martian soils and rocks.

    The vast water icecaps at the poles may be the source. The
    thickness of the icecaps themselves may be enough to bottle up
    geothermal heat from below, increasing the temperature at the
    bottom and melting the bottom layer of the icecaps, which then
    could feed a global water table.

    On the other hand, there is evidence that about a million years
    or so ago, Mars' axis was tilted about 35 degrees, which might
    have caused the polar icecaps to evaporate and briefly create
    enough water in the atmosphere to make ice stable planet-wide. The
    resultant thick layer of frost may then have combined chemically
    with hydrogen-hungry soils and rocks.

    "We're not ready yet to precisely describe the abundance and
    stratigraphy of these deposits, but the neutron spectrometer shows
    water ice close to the surface in many locations, and buried
    elsewhere beneath several inches of dry soils," Feldman said.
    "Some theories predict these deposits may extend a half mile or
    more beneath the surface; if so, their total water content may be
    sufficient to account for the missing water budget of Mars."

    In fact, a team of Los Alamos scientists has begun a research
    project to interpret the Mars Odyssey data and their ramifications
    for the history of Mars' climate. The project is funded through
    the Laboratory Directed Research and Development program - which
    funds innovative science with a portion of the Laboratory's
    operating budget - and seeks to develop a global Martian hydrology
    model, using vast amounts of remote sensing data, topography maps
    and experimental results on water loading of minerals.

    Members of the Planetary Science team at Los Alamos working with
    Feldman on the Odyssey project include Bruce Barraclough, David
    Bish, Dorothea Delapp, Richard Elphic, Herbert Funsten, Olivier
    Gasnault, David Lawrence, G. McKinney, Kurt Moore, Robert Tokar,
    Thomas Prettyman, David Vaniman and Roger Wiens as well as Sylvestre
    Maurice of the Observatoire Midi-Pyrénées (France), S.W.
    Squyres of Cornell University, and Jeff Plaut of the Jet Propulsion

    Los Alamos' neutron spectrometer, a more sensitive version of the
    instrument that found water ice on the moon five years ago, is one
    component of the gamma-ray spectrometer suite of instruments aboard
    Odyssey. W.T. Boynton of the University of Arizona leads the
    gamma-ray spectrometer team.

    The neutron spectrometer looks for neutrons generated when cosmic
    rays slam into the nuclei of atoms on the planet's surface, ejecting
    neutrons skyward with enough energy to reach the Odyssey spacecraft
    250 miles above the surface.

    Elements create their own unique distribution of neutron energy - fast,
    thermal or epithermal - and these neutron flux signatures are shaped
    by the elements that make up the soil and how they are distributed.
    Thermal neutrons are low-energy neutrons in thermal contact with the
    soil; epithermal neutrons are intermediate, scattering down in energy
    after bouncing off soil material; and fast neutrons are the
    highest-energy neutrons produced in the interaction between high-energy
    galactic cosmic rays and the soil.

    By looking for a decrease in epithermal neutron flux, researchers can
    locate hydrogen. Hydrogen in the soil efficiently absorbs the energy
    from neutrons, reducing their flux in the surface and also the flux that
    escapes the surface to space where it is detected by the spectrometer.
    Since hydrogen is likely in the form of water-ice at high latitudes, the
    spectrometer can measure directly, a yard or so deep into the Martian
    surface, the amount of ice and how it changes with the seasons.

    The Los Alamos expertise in neutron spectroscopy stems from longtime
    nuclear nonproliferation work at the Laboratory, funded by the U.S.
    Department of Energy's National Nuclear Security Administration. The
    ability to measure and detect signatures of nuclear materials is a
    vital component of the Laboratory's mission to reduce the threats
    from weapons of mass destruction.

    Mars Odyssey was launched from Cape Canaveral Air Force Station in
    April 2001 and arrived in Martian orbit in late October 2001. During
    the rest of the spacecraft's 917-day science mission, Los Alamos'
    neutron spectrometer will continue to improve the hydrogen map and
    solve more Martian moisture mysteries.

    Jet Propulsion Laboratory, a division of the California Institute of
    Technology in Pasadena, manages the Mars Odyssey mission for NASA's
    Office of Space Science in Washington, D.C. Investigators at Arizona
    State University in Tempe, the University of Arizona in Tucson and
    NASA's Johnson Space Center, Houston, operate the science instruments.
    Additional science partners are located at the Russian Aviation and
    Space Agency and at Los Alamos National Laboratories, New Mexico.
    Lockheed Martin Astronautics, Denver, the prime contractor for the
    project, developed and built the orbiter. Mission operations are
    conducted jointly from Lockheed Martin and from JPL.

    Los Alamos National Laboratory is operated by the University of
    California for the National Nuclear Security Administration (NNSA)
    of the U.S. Department of Energy and works in partnership with NNSA's
    Sandia and Lawrence Livermore national laboratories to support NNSA
    in its mission.

    Los Alamos develops and applies science and technology to ensure the
    safety and reliability of the U.S. nuclear deterrent; reduce the
    threat of weapons of mass destruction, proliferation and terrorism;
    and solve national problems in defense, energy, environment and

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