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Thread: New Risk from Supernovas

  1. #1
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    New Risk from Supernovas

    Long-term exposure to blue-enhanced light would interfere with life
    Well, it took me a while to get past all the known data and the doom and gloom, then the "no not really bad" to get to the story.
    Those who study chronobiology, or the effects of biological timing, have found that low levels of blue light can strongly affect the endocrine systems of mammals by causing physiological and alerting responses. Blue-enhanced light is associated with reduced levels of melatonin production and affects circadian rhythms. For these reasons, it is sometimes prescribed to counteract seasonal affective disorder (SAD) or winter depression.
    And Insomnia... We're doomed.

  2. #2
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    Quote Originally Posted by NEOWatcher View Post
    We're doomed.
    BluBlockerTM sunglasses! As seen on TV!!
    0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 ...
    Skepticism enables us to distinguish fancy from fact, to test our speculations. --Carl Sagan

  3. #3
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    Gee--given the bluishness of old television tube light, why have so many fallen asleep in front of the TV?

  4. #4
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    The article says this blue glow would last about half a year. Not much at all. And would only effect a tiny fraction of the world's population. So it's a minor issue, even assuming EC goes haywire anytime soon.

    EDIT: (And for the record, the title really should be "Newly Recognized Risk from Supernovas".)
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

  5. #5
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    There are a number of things about this that may be overkill. Consider these...

    The peak radiation output of the Sun is in the blue, 485nm IIRC.

    Our atmosphere will knock out about 20% or more of the blue when it is overhead (added: ~45% reduction at ~45 deg. elevation). Except for violets, the blues will be the weakest when the sn is near the horizon.

    If it is bright enough, it will not appear blue. Once our color cones are maxed-out, all is white. The Sun could be blue, or yellow, and an astronaut would never know since, in space, the Solar flux exceeds greatly the eye's color cones threshold. [Of course, that is only when we foolishly stare at it, admittedly. ]

    Not speaking for other heliochromologists, the Sun is not blue or white. I know because I stay up late at night involved with this blue-background forum.
    We know time flies, we just can't see its wings.

  6. #6
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    Canadian lab rats sickened by exposure to supernovae, successfully treated with cyclamates! Film at 11!

  7. #7
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    Quote Originally Posted by NEOWatcher View Post
    Long-term exposure to blue-enhanced light would interfere with life
    The article only mentions "mammal" "endocrine systems." I hear there is a reptile and fish demonstration against this "classist" insinuation that life is equivalent to mammalian life!
    As above, so below

  8. #8
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    Quote Originally Posted by George View Post
    There are a number of things about this that may be overkill. Consider these...

    The peak radiation output of the Sun is in the blue, 485nm IIRC.

    Our atmosphere will knock out about 20% or more of the blue when it is overhead (added: ~45% reduction at ~45 deg. elevation). Except for violets, the blues will be the weakest when the sn is near the horizon.

    If it is bright enough, it will not appear blue. Once our color cones are maxed-out, all is white. The Sun could be blue, or yellow, and an astronaut would never know since, in space, the Solar flux exceeds greatly the eye's color cones threshold. [Of course, that is only when we foolishly stare at it, admittedly. ]

    Not speaking for other heliochromologists, the Sun is not blue or white. I know because I stay up late at night involved with this blue-background forum.
    George. This site says yellow-green for peak output. see:http://209.85.173.104/search?q=cache...lnk&cd=7&gl=us

  9. #9
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    Quote Originally Posted by trinitree88 View Post
    George. This site says yellow-green for peak output. see:http://209.85.173.104/search?q=cache...lnk&cd=7&gl=us
    They are clearly in error. They discuss Wiens displacement but don't bother to apply it accurately. If they did they would get a peak Planck wavelenth of 0.483 microns (blue) [using their own temp. value of 6,000K]. They rounded off and simply stated 0.5 microns. Yet, even if we allow for approximation, 0.5 micron is not near yellow-green. It is light blue (cyan).

    The actual peak as seen in space (AM0), using the Wiehrli '85 data set, is 450nm (0.45 micron). This is blue-violet. However, the energy level is relatively high from 445nm to 500nm (blue to cyan).

    In fairness, in terms of photon flux (how the eye sees color) the peak is in the yellow, though not yellow-green. But this is not a peak. It's a pimple! The photon flux distribution is flat as a pancake, maybe with a little slightly raised pecan varriance. The blue region, surprisingly, is not near as flat as the rest of the visible spectrun due to the linear E=hf reduction.

    The Sun is white. The central zone of the Sun is very likely white only. The limb is definetly white, though it is 1400K cooler than the 6400K central zone.
    We know time flies, we just can't see its wings.

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