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NASA's closer to knowing why Mars' surface is cold and dead

It looks like NASA's figured out one of the reasons why Mars isn't fit for human -- or any other kind -- of life. The space agency held another press conference to discuss why Mars has turned from what was thought to be a wet, lush planet (that might have contained surface life) into a cold, desolate place. The likely culprit? Solar winds. With a little help from the MAVEN probe (Mars Atmosphere and Volatile Evolution), researchers were able to figure out how much of the planet's atmosphere is being stripped away by solar winds -- around 1/4 pound of gas every second. Bruce Jakosky, MAVEN's principal investigator at the University of Colorado, likened the atmospheric loss to taking a small amount of coins out of a cash register every day -- at first it's insignificant, but over time can have a big impact.

Scientists found that the atmosphere breaks down quicker when solar storms occur. Charged particles that come from the Sun shoot out towards the planets at about one million miles per hour. The magnetic field carried by the particles flows past Mars and creates an electric field which speeds up other electrically charged atoms and shoots them into space. Researchers think that these storms were much stronger billions of years ago when the Sun was younger, which more than likely sped up the process of degrading Mars' atmosphere creating the arid land we know today.

[Image credit: NASA]