It may be snowing carbon dioxide on Mars
This is a map of Mars' south pole ice cap, showing of small-grain carbon-dioxide ice deposits are distributed. They appear to have come from snowfall.
September 11th, 2012
05:21 PM ET

It may be snowing carbon dioxide on Mars

It's not time to get out the sleds and shovels in the United States, but all the way over on Mars, snow may be falling on the south pole.

There appears to be snow falling on the Red Planet that is not made of water, however. This is frozen carbon dioxide, which can only exist at extremely low temperatures - namely, about -193 degrees Fahrenheit.

New data to be published in the Journal of Geophysical Research explores evidence for carbon dioxide snowfalls that come from clouds around the Martian south pole during the winter. The data comes from the Mars Reconnaissance Orbiter.

This is the only example of carbon-dioxide snow falling that we know about in the solar system, NASA said Tuesday.

We know about water-ice snow on Mars too from NASA's Phoenix Lander, which observed it in 2008.

Read more about this from NASA

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Filed under: In Space • Mars
soundoff (19 Responses)
  1. Anura

    "This is frozen carbon dioxide, which can only exist at extremely low temperatures – namely, about -193 degrees Fahrenheit."

    I believe, that the author of the above article got -109.3F mistaken as -193F. Carbondioxide freezes between -108.7 and -109.3F (-78.2 to -78.5 °C)

    September 15, 2012 at 12:36 pm |
    • paulhayne

      At the atmospheric pressures of Mars (about 6 millibars), carbon dioxide freezes directly from vapor at about 148 K, or -125 C, or -193 F

      May 2, 2013 at 5:41 pm |
  2. Rein

    All this science "knowledge" will not bring the forgiveness and grace of the Lord God. CO2 rain will be replaced by a rain of hellfire upon the sinners who feel lust in their perverted space cosmos. Romney will cut this misguided funding, and the rover will be turned into rosaries, my brothers.

    September 14, 2012 at 10:55 pm |
    • DEJ

      Didn't Obozo cut NASA funding to begin with? I think you have your politicians mixed up!

      September 15, 2012 at 10:07 am |
    • ~Mike

      Have another glass of Kool-aid Rein...

      September 15, 2012 at 8:00 pm |
    • John Doe

      You are so diluted...You, Romney, and your God should sit in a garage together, shut the garage door turn on the car and kill yourselfs....its people like you that slow our evolution...Science is the key, and your probably mad because its already dis proven your bible and your boy Jesus...

      September 16, 2012 at 12:07 am |
      • LB

        @John Doe
        What does Romney have to do with Rein's diluted remarks?

        September 16, 2012 at 12:48 pm |
    • Marint

      Hey I heard the space ship with the angels sent here to save good Christians is in orbit but you must hurry, they told me in order to get in the spaceship you will have to jump from the highest bridge you can find, God told me in person, don't dare question him ... so go hurry, will meet you up there....

      September 17, 2012 at 4:03 am |
    • Paul Hoffman

      Dear Rein,

      Please do not ever offer your opiions again, The world will be a better place.

      Thanks !

      September 17, 2012 at 3:39 pm |
  3. Piranha

    Mars composition is desert and dry ice, Hell frozen over.

    September 13, 2012 at 5:52 pm |
  4. Daniel

    The freezing point of CO2 is -109 F, not -193 F. Look it up on google.

    September 13, 2012 at 4:31 pm |
    • Matt

      The freezing and boiling points of any chemical is dependent on the pressure that it is under. Since the atmospheric pressure on Mars is so much lower than Earth's, CO2 will freeze at a lower temperature on Mars than on Earth.

      September 14, 2012 at 1:09 pm |
  5. kanga

    the temp of -193 f? thats not so bad, isn't that normal temps in Canada.Lol

    September 13, 2012 at 11:57 am |
  6. Greg

    This is old news. We've known that Mars's south pole is covered with frozen carbon dioxide for a very long time now. We've seen the ice cap get bigger and smaller with the seasons, so we knew that it must "snow" frozen CO2 during the southern hemisphere's winter. This pretty picture is merely the first time we've gotten good, specific weather data – including the size of the ice grains – while it was happening.

    Our next step on Mars is a "sample return" mission – a spacecraft that will bring some rocks and soil from Mars back to Earth, for detailed study. As far as I know, NASA isn't planning such a mission yet. >sigh<

    September 13, 2012 at 7:20 am |
  7. MDAT

    Simple.Mars has a Co2 atmosphere.In cold areas some of it will change to ice.

    September 12, 2012 at 3:03 pm |
    • Except

      Ice is made of it we could convert CO2 to water that would be a trick.

      September 12, 2012 at 3:48 pm |
      • MDAT

        We can't do that.If you split it you would get carbon and oxygen.You would need hydrogen for it to be turned into water.

        September 12, 2012 at 3:50 pm |


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