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Solar Flare Interference From 45k Lightyears Away

Posted by CmdrTaco on from the duck-the-flares-are-coming dept.

Wan2Be writes "Nasa has a story about a solar flare on Aug. 27 that affected our planet with radio bounces and blackouts - but it wasn't from old Sol, it was from SGR 1900+14, a neutron star about 45,000 light years away. "

11 of 154 comments (clear)

  1. Re:45,000 light years away? by vadim_t · · Score: 2, Informative

    And how exactly would they see it coming?

    Somebody correct me if I'm wrong, but AFAIK it works like this: Something 1 light year away blows up. 1 year later we see it blowing up. We couldn't see it blow up when it actually did, because the light from the event didn't reach us yet!

    So, how exactly are going scientists to see that before it reaches us?

  2. Re:Have they got the numbers right ? by Anonymous Coward · · Score: 4, Informative

    Actually, since we are talking about electromagnetic radiation, the energy will drop with the sqaure of the distance, not the cube. This might impact your calculations just a little bit.

    - GK

  3. Re:Have they got the numbers right ? by Crashmarik · · Score: 2, Informative

    Square of the distance not cube. Its an inverse square law. Inverse cube is for things like magnetic fields that are generated by dipoles.

  4. This was 5 years ago by Skapare · · Score: 3, Informative

    When I saw this story on Slashdot, I was trying to think back to having experienced any radio effects back on 27 August, but I couldn't recall any. Then I read the article and saw that it was really a 1998 event only being written about just now, 5 years later. From an academic study perspective, that's fine. The article is about these effects in general and the study being made of them. The 27 August 1998 event was merely an example of one that played a significant role. And as they report, there have been 10 of these since, and the potential for much larger ones.

    --
    now we need to go OSS in diesel cars
  5. Re:Not only that by Anonymous Coward · · Score: 2, Informative

    The article talks about two unrelated events about a day apart. The first was from our sun. That was the one which registered the solar protons. The second one was an extrasolar event which did not register any protons.

  6. Re:Just to clear something up by saden1 · · Score: 1, Informative

    How do you know it was on August and on the 27th?

    According to my calculations and if one assume Warp 9 is possible it happened 5000 years ago. I would give a more definitive date but the Julian calender starts at 4713 BC.

    --

    -----
    One is born into aristocracy, but mediocrity can only be achieved through hard work.
  7. Re:45,000 light years away? by mindstrm · · Score: 2, Informative

    I think you need to re-evaluate what you think space is made of, and how the speed of light is relevant.

    We can't see "ripples" Because they woudl have to move faster than the speed of light to get to us before the event itself did... the maximum speed any effect on the universe from that event moves outwards is the speed of light. Period. Gravitational.. the imaginary "ripples" you think you would see, everything.. NO effects can be detected any faster than that.

    In fact, from our perspective, it didn't happen until we see it.

    Now, speed of light in a vacuum, yes, is a limit.. what "stuff" do you think it travelled through? Do you think the interstellar dust somehow significantly slowed down the light from the event, yet would allow the effects of that light to ripple towards us faster? Makes no sense.

  8. Thats "effected" not "affected" by Archeopteryx · · Score: 1, Informative

    Sister Anella would have taken ten point off for a screwup like this...

    --
    Dog is my co-pilot.
  9. Re:Hams were first to notice by Anonymous Coward · · Score: 1, Informative

    Sunspot activity has an effect on the signals they can send and receive. During an 11 year sunspot cycle peak, I was able to send and receive signals from Europe in the afternoon. These flares affect the ionosphere, and allow the signals to bounce along the underside, and reach distant parts of the globe. So, the hams know something is going on when the signals start coming in from distant areas that they normally do not get.

  10. Re:Just to clear something up by Viadd · · Score: 3, Informative
    In this case, the ionospheric disturbance was from the X-rays and gamma-rays (high energy photons, travelling at lightspeed) hitting the atmosphere. The main part of the pulse was a huge spike of gamma-rays, followed by bright tail of periodically varying gamma-rays (with the neutron star's ~5 second rotation period) decaying in the next few minutes.

    If there were a pulse of sub-light particles coming from the SGR, they would be no longer be a short pulse when they reached Earth fro two reasons: The particles travelling at 90% of lightspeed would come many years before the particles travelling at 89.99% of lightspeed; And the tangled magnetic field of the Galaxy would bend their paths all over the place so they'd be travelling different distances.

  11. Re:Cajun Blackened Astronaut by Viadd · · Score: 4, Informative
    What sort of radiation dose would an astronaut receive if he was located outside the Van Allen Belt?
    I worked it out once. This particular SGR burst would have given an astronaut the equivalent of a dental X-ray. Pretty potent for half-way across the Galaxy, but not a health hazard. And the Van Allen Belts wouldn't have provided any shielding because the X-rays/gamma-rays are uncharged photons, which aren't affected by Earth's magnetosphere.

    Solar flares are most deadly because of the proton flux, which would be blocked, but which travels much slower than lightspeed. If you see X-rays from a solar flare, it tells you that you have an hour or so to get into a shielded environment before the big storm hits.