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Sand Dunes On Mars In Motion

TheNextCorner writes with news that NASA's Mars Reconnaissance Orbiter has detected ripples and shifts in the sand dunes on Mars, which means the surface of the planet is more dynamic than previously thought. Planetary scientist Nathan Bridges said, "Mars either has more gusts of wind than we knew about before, or the winds are capable of transporting more sand. We used to think of the sand on Mars as relatively immobile, so these new observations are changing our whole perspective." The article explains, "The air on Mars is thin, so stronger gusts of wind are needed to push a grain of sand. Wind-tunnel experiments have shown that a patch of sand would take winds of about 80 mph to move on Mars compared with only 10 mph on Earth. Measurements from the meteorology experiments on NASA's Viking landers in the 1970s and early 1980s, in addition to climate models, showed such winds should be rare on Mars."

2 of 55 comments (clear)

  1. Nah, not wind by bhcompy · · Score: 5, Funny

    It's just the sandworms. I hope the rover that goes to the sand desert regions has a thumper

  2. Re:Controlled for all factors? by Baloroth · · Score: 5, Informative

    Took me about 30 seconds of computation to figure out: probably. KE=1/2 M*v^2. M(mars atm)=~.01M(earth atm). v(e)=10MPH, v(m)=80MPH. Works out (very roughly) to the same KE needed if you account for the reduced gravity. I'm certainly no fluid dynamicist though.

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