The mysterious dark splotches of Mars

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The dark splotches of Mars

Cool image time! The image on the right, cropped and reduced in resolution to post here, shows one particular dark splotch in a region with several similar dark areas.

Geologists aren’t quite sure what to make of the dark splotch in the middle of this image, one of several similar dark splotches that extend east and west for over 100 kilometers. From measurements made in infrared, this and other dark splotches have what we call “high thermal inertia,” meaning that it heats up and cools down slowly. Scientists use thermal inertia to assess how rocky, sandy, or dusty a place is. A higher thermal inertia than the surrounding area means it’s less dusty.

The image below the fold shows at full resolution the area indicated by the white box. It provides me no clue as to the cause for the darker color. I think we can speculate all we want, but the truth is that we simply don’t have enough information. We need a closer look, including boots on the ground, to figure this out.

Close-up on the dark splotch



  • BSJ

    The bottom right hand portion of that image looks ‘Glacial’ to me. Wish they could use some penetrating RADAR on it…

  • Orion314

    Mars always seems to be stranger than the best SF can imagine. But I still think the moon is the 1st place to set up shop.

  • LocalFluff

    Unless there’s a smooth depression there, the dark blotch (dark because it consists out of fine dust, I suppose) doesn’t seem to care much about the shape of the landscape. Which seems funny when wind is the natural candidate for making something like this.

    Off topic but still on Mars. A lecture about habitability of caves, on Earth and Mars. Sounds like your kind of topic, Robert.

  • Louis Seal

    Looks like a waste dump to me

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