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Incredible Images of the Sun

Posted by michael on from the it's-the-yellow-thing.-outside. dept.

shelterit writes "A new swedish telescope facility in La Palma uses a new technology to remove the blurriness of the atmosphere to snap new and astonishingly sharp images of the sun. Want to have a closer look at the surface of it? Reminds me of paintings I did as a kid."

3 of 239 comments (clear)

  1. GIFs??? by ergo98 · · Score: 5, Insightful

    What in the world are they thinking putting them up as 3MB GIFs? I understand the need for super accuracy for some purposes, hence the need for lossless TIFFs, but there should be JPEGs for people who don't need perfect reproductions: The smooth gradients lend themselves to JPEG compression.

  2. Re:Hmm by two_ply · · Score: 4, Insightful
    "these images are sharper than even current space-based solar observatories can produce. "

    By using new technology earth based observatories have made an advance over *current* space based observatories. Doesn't it follow that by using the same advances space based observatories will exceed earth based ones once they can be implemented? Also, they're be no need for correcting for the atmosphere ...

  3. Re:Adaptive Optics by CharlieO · · Score: 4, Insightful

    And the most fun to be had with an Adaptive Optics system is if it uses a laser generated guide star.

    Then you can chuck a frisbee like object through the beam and watch it get zapped :)

    Did I say this was seriously frowned on, I think I should :)

    Adaptive Optics in a Nutshell:

    1) You use a single point source as a reference.
    2) You know the aberation caused by the atmosphere will spread the point image when you receive it.
    3) You know that as your source is a point source, then the resultant spread in your image is entirely due to aberation, so use the image to calculate the Point Spread Function
    4) Using the PSF apply a correction to the light path by altering something in the imaging system, usually a mirror.
    5) Repeat several hundred times a second

    Of course the great side effect is this also removes distortion caused by the imaging system itself, allowing you to use bigger mirrors with a lower tolerance than you otherwise might be able to do.

    Originally point sources were strong and predictable stars in the field of view that you wanted - hence the term 'guide stars'

    With a laser generated guide star you project a spot onto the upper surface of the atmosphere with a powerful laser of an appropriate frequency - close to your obsering frequency, but far enough out that you don't effect the observation. The subtlety here is to account for the fact that the point source will be spread twice, once on the way up and once on the way down.

    Anyone working in AO I apologise to for the somewhat oversimplification - follow the links in the parent to better details if your interest is fired.