Credits - NASA/JPL-Caltech/ASU/MSSS/J. Roger (landru79)

    • paulhammond5155@lemmy.worldOP
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      23 days ago

      They are mostly seasonal.

      Those shown here are from several different missions.

      They are rarely easy to see in the images, as they are so feint that you need to over-process the images to make them show, that’s why the images are usually grainy

      • vatlark@lemmy.world
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        23 days ago

        Interesting, if they are so hard to detect in images, I wonder how the dust devils are initially identified.

        • paulhammond5155@lemmy.worldOP
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          23 days ago

          They take specific sets of images from time to time to search for dust devils and dust lifting events. These are acquired a few seconds apart so they can form animations if any activity is seen. Automatic processes can easily be set up to review the images and alert operators of any positive hits.

          Those sequences are planned more frequently in the seasons and at the time of day when winds are expected to be high enough to create dust devil etc. They don’t catch dust devils in every sequence, but when they so the science team can estimate the speed, how high they go etc. This gives them a lot of data on the climate on mars.

          They have even recoded the sound of a vortex (probably a dust devil) passing over Perseverance rover. Here’s a video that has the sound https://youtu.be/lICyLnT7iPo