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Largest Sun Spot In Nine Years Now Viewable

Posted by timothy on from the hang-on-to-your-cell-phones dept.

Mazarin writes: "The BBC has an interesting article about the largest sun spot to come around in nine years. 'The spot, which is moving towards the centre of the Sun's disk, covers an area a dozen times larger than the entire surface of the Earth.' The article goes on to talk about other sun spots that have caused minor disturbances and gives a nice little warning about not looking at the sun during this time."

8 of 130 comments (clear)

  1. Re:Is looking at the sun really bad? by Happy+Fun+BaII · · Score: 3

    Well, it's more likely to cause blindness than masturbation... ;)

  2. Sunspot info site by Twid · · Score: 4

    Although it's geared towards kids in school, NASA has a great site on Sunspots here.

    There is also an interesting article on the recent coronal mass ejection here.

    Also read about the cold summer of 1816 here. It is theorized that the earth was extra cool because of sunspot activity.

    Fun stuff... brings out the amateur scientist in me.

    -Todd

    --
    - "When you want something with all your heart, the entire universe conspires to give it to you" -Paulo Coelho
  3. Feynman says... by rjh · · Score: 5

    In Surely You're Joking, Mr. Feynman! (are there two Ns or just one in his name? I always forget), Richard Feynman talks about the Trinity nuclear test. He was the only person to look at the nuclear bomb directly, and suffered no permanent eye damage.

    According to Feynman (or at least, what's written in his book), it's the ultraviolet light which cooks your retinas, and that visible light simply won't do it no matter how intense it is. He took the simple precaution of watching the nuclear blast through a truck windshield, which is UV-opaque. While he had a big purple blotch in his visual field for several minutes afterwards, he did manage to watch a nuclear blast without permanent damage, which I think is pretty damn cool. :)

    From my own experience, I can submit anecdotal evidence which supports Feynman's UV-is-the-problem hypothesis. Once, while working in a laser holography lab, I wound up getting an eyeful of HeNe. While I was damn near blind in that eye for ten minutes afterwards, I had no permanent effects.

    ObWarning: I am not a competent eyecare professional, and don't try either of these stunts at home. Really. Especially not the nuclear one. :)

    1. Re:Feynman says... by deglr6328 · · Score: 4

      i'm betting those HeNe tubes were less than 5 milliwatts though. IMHO saying visible light simply won't damage your eyes no matter how intense it is, is just plain false.

      the energy of a laser beam can be intensified up to 100,000 times by the focusing action of the eye. If the irradiance entering the eye is 1 mW/cm2, the irradiance at the retina will be 100 W/cm2.

      so if you have anything over 30mW, no matter what wavelength(except far ultraviolet and mid to far infrared which will cause burns to the cornea) in a direct beam impact of the eye you are almost absolutely sure deposit enough energy in your retina to cause fast heating and burn even considering the blink reflex.

      --
      - "Hear that?! The percolations are imminent! Cease your ingress!"
  4. Is looking at the sun really bad? Yes by fence · · Score: 3

    Ok, I'll bite on this one.

    in '77 when I was a kid, there was an eclipse of the sun on the west coast of the United States.
    My sister and I were psyched about it, and our parents talked to us about how to view the eclipse and we made pin-hole viewers, etc...

    To make a long story even longer, my sister looked at the eclipse several times--trying to focus on the sun to see the eclipse better.

    That day she had a blind spot form right in the center of her vision. She didn't tell anyone about it, hoping that it would go away. Finally after several days she 'fessed up about the blind spot and she went to an eye doctor.

    The doctor had been inundated by people with stories similar to hers...he said that she should consider herself lucky that she hadn't blinded herself.

    Imagine how tough it would be to have a blind spot directly in the center of your vision. It is a dark spot that you can't look around. Imagine trying to focus on someone's face and seeing nothing.

    So, Yes, looking at the sun IS really bad
    ---
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  5. kinda by Uberminky · · Score: 4
    Amateur radio operators ("hams") will be familiar with this.. Basically, when there's more sunspots, the upper atmosphere is ionized more than usual. This makes sky-wave propagation (radio waves bouncing off the upper atmosphere, usually in the F2 region) much better because it defracts more. Makes it easier for the radio waves to bounce off of the upper atmosphere. So in times when there are lots of sunspots, DXing (talking long distance) is better. Of course this is basically only relevant during the day, because at night the ions created by the UV from the sun combine with the free electrons and neutralize (and are this no longer ions). Everyone feel free to rip this to pieces, I'm still studying for my ham radio exam.. ;)

    . ._ _ .__. ___ ___ ._ _. _.. _. .. .

    --

    The streets shall flow with the blood of the Guberminky.

  6. Re:Current SOHO Image by Baldrson · · Score: 3
    Here is the current SOHO image.

    Here is its thumbnail.

    --
    Seastead this.
  7. 9:15 Personal Note by BMIComp · · Score: 3

    When I was a little kid, my mother told me not to stare into the sun, so once when I was six I did. The doctors didn't know if my eyes would ever heal, I was terrified, alone in that darkness. Slowly, daylight crept in through the bandages, and I could see. Something else had changed inside me. That day I had my first headache.