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First Pictures From Mars Phoenix Lander

Now that the solar panels have been deployed, the Mars Phoenix Lander has begun sending back pictures of the red planet to the hungry space geeks of earth. In just a few weeks the claw will deploy and they'll start digging a hole. The scientists expect to use the dirt to construct a little sand castle which they will defend with several GI Joe action figures, and a bald barbie stolen from their sisters. Oh, and maybe find water or bacteria.

4 of 211 comments (clear)

  1. Re:Colour? by Chmcginn · · Score: 5, Informative

    It's more scientifically useful to put a really good black & white camera onboard, and then include some filters, than to put a color camera.

    IIRC, pretty much all the color images from previous landers are composites of multiple images with different filters, making a human-eye approximation.

    --
    Have you been touched by his noodly appendage?
  2. Somewhere in the red circle... by Chmcginn · · Score: 5, Informative

    Here. The blue ellipse was the intended landing zone, the red the actual, and the green box was... umm... a Martian football field? I dunno.

    --
    Have you been touched by his noodly appendage?
  3. Re:Interesting Object? by JambisJubilee · · Score: 5, Informative

    When an object is too bright for a CCD camera, it causes excess charge to "bloom" into adjacent pixels. It's a common artifact.

  4. Re:Colour Imaging? - Cost and Compromise by Tablizer · · Score: 5, Informative

    As far as space missions and human-friendly color images, the bottom line is that transmission of images is expensive. Thus, they don't use the human-friendly wavelengths very often. However, there are various mathematical ways to approximate such using the other filters plus some sample calibrations, and this is usually what we see in press-release images from most missions.

    For example, the rover missions usually use infrared filters instead of "red" filters for that end of their range; but they can use that one to approximate the red filter with some adjustments.

    I suspect they will do similar things with this mission once it gets up to speed. The preliminary color images are 2-filter approximations. If they do what the rovers did, they'll use 3 filters that don't match human eyesight but compensate with digital processing to give us "human" approximations. They'll be better than these early 2-filter approximations.

    If you as a human are upset at this approximation; fish, birds and reptiles will be even more angry because they have 4 color cones instead of 3. (We'd probably have four if our mammalian ancestors were not nocturnal. Damned those mammal-squishing dinosaurs who made us hide in the darkness! I wish meteors on you for limiting our color!)