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Mars Space Science

A Third of Mars Could Have Been Underwater 167

Matt_dk writes "An international team of scientists who analyzed data from the Gamma Ray Spectrometer onboard NASA's Mars Odyssey reports new evidence for the controversial idea that oceans once covered about a third of ancient Mars. 'We compared Gamma Ray Spectrometer data on potassium, thorium and iron above and below a shoreline believed to mark an ancient ocean that covered a third of Mars' surface, and an inner shoreline believed to mark a younger, smaller ocean.'"
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A Third of Mars Could Have Been Underwater

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  • Potassium Salts (Score:5, Informative)

    by praedictus ( 61731 ) on Tuesday November 18, 2008 @10:53AM (#25801421) Journal
    Makes some sense to see potassium anomalies in the old basins if there was water there which has since been evaporated, with the concentration increasing toward the centres, as potassium salts are somewhat more soluble than their sodium equivalents, theyd be the last left to precipitate out. Thorium on the other hand is usually residual, at least here on Earth, and tends to concentrate along shorelines and riverbeds due its high density and low solubility.
  • Re:Why water? (Score:2, Informative)

    by praedictus ( 61731 ) on Tuesday November 18, 2008 @11:31AM (#25801889) Journal
    Re Ocean ridge volcanics: The basalt and associated rock from spreading centres tend to be Low-K, Low Th and high Fe. Potassium and Thorium in igneous rocks tend to be associated with granites or the types of volcanoes that go "BOOM!" rather than produce extensive flows.
  • Re:To prove it... (Score:4, Informative)

    by avgjoe62 ( 558860 ) on Tuesday November 18, 2008 @01:47PM (#25804425)
    Don't make me come out there and beat you with the sarcasm tag... Kids these days. Can't recognize a smart ass when they come and slap them in the face.
  • by JerryLove ( 1158461 ) on Tuesday November 18, 2008 @01:52PM (#25804549)

    Whatever caused the devastation on Mars, could be avoided on Earth with the correct approach to discovering the truth.

    Mars is devistated?

    Mars has no water/atmosphere because A)It is small and B)It lacks a magnetosphere (which is because its core has cooled which is 1) because it is small and 2) because it lacks a large moon). With no pressure, water sublimates. With no tectonic activity to introduce more, and less gravity to attract more from space, it dried up. Distance+no greenhousing also means its cold.

    For the reasonable future, Earth has none of these problems. Our current threat is "random catastrophy" or "runaway greenhouse" (look at Venus, not Mars). If we get past those, then we can worry about (as mentioned by someone else) the increasing luminosity of the sun.

The intelligence of any discussion diminishes with the square of the number of participants. -- Adam Walinsky