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Mysterious Martian Grooves Carved by Dry Ice Chunks?

It appears Mars may one day become a premier extreme snowboarding destination.

NASA research released this week indicates that mysterious, long narrow grooves carved into the slopes of giant Martian sand dunes may in fact be generated by gliding chunks of dry ice. Scientists have observed the grooves via images from NASA’s Mars Reconnaissance Orbiter and other instruments for about a decade. (Also see “Mars Snow Falls Like Dry Ice Fog.”)

martian gully picture
An image from the Mars Reconnaissance Orbiter shows grooves now believed to be created by dry ice blocks surfing down the slopes. Image courtesy NASA/JPL-Caltech/Univ. of Arizona/EPA

“I have always dreamed of going to Mars,” study leader Serina Diniega, a planetary scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California, said in a NASA statement.

“Now I dream of snowboarding down a Martian sand dune on a block of dry ice.”

Bizarre Grooves Explained

Called linear gullies, these bizarre grooves stretch down hillsides for up to 1.2 miles (2 kilometers) and are only a few meters wide, with raised banks or levees along the sides. (See another picture of Martian gullies.)

Diniega and her team believe these gullies are formed as the Martian surface warms during springtime, when a layer of carbon dioxide frost—commonly referred to as dry ice—vaporizes. This causes blocks of dry ice to break off and glide down the slopes on a cushion of carbon dioxide vapors, cutting the visible linear gullies into the sand, according to the study, published online June 11 by the journal Icarus.

They came to this conclusion after analyzing before-and-after images from different seasons showing the formation of new gullies and even spotting bright, white objects within the grooves.

To support the theory, the team conducted experiments here on Earth by sliding dry ice down sand hills in Utah and California, which replicated perfectly the features seen on Mars—despite differences in air pressure and temperature.

As final evidence of these surfing ice blocks, researchers noticed multiple pit formations at the bottom of the hills, which they think are where the blocks came to rest before turning into gas.

Follow Andrew Fazekas, the Night Sky Guy, on Twitter and Facebook.


  1. Frank Norton
    San Francisco, CA USA
    June 16, 2013, 11:35 pm

    Although Earth’s atmosphere has only some 300 parts per million of CO2, one would think that a small portion of this would form dry ice on the polar ice caps. Especially since the heaver CO2 molecules are located nearer the ground. One never hears of this. Perhaps in past times when the atmosphere contained some 3,000 CO2 PPM this was more likely to have happened. Interesting Mars pictures any way.

  2. bayu
    June 15, 2013, 3:07 pm

    mybe megatron and optimus prime do that..

  3. Mouad'dib
    June 13, 2013, 5:26 pm

    Paumanok is right. They are in fact sand worms. And now, for your safety, may I advise you to run to the nearest rock!

  4. Ima Ryma
    June 13, 2013, 2:51 am

    Earthlings have pondered oh so long
    As to whether there’s life on Mars.
    One day humans with a big tong
    Will ride dry ice under the stars.
    Dry ice chunks are like ponies wild,
    Sliding grooves into dunes of sand,
    Beckoning to that future child
    For adventure in a new land.
    Perhaps a new Olympic sport –
    Sand boarding on chunks of dry ice,
    Assuming the weather report
    Says that Mars day will be quite nice.

    Chunks of dry ice on a sand dune
    Means Disney Mars will open soon.

  5. aidn
    June 12, 2013, 5:52 pm

    looks more like the side of a whale than a sand dune

  6. Paumanok
    June 12, 2013, 3:54 pm

    It may just be Paul Atreides riding sand worms.