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Solar Flare Danger

  1. Jul 15, 2010 #1
    What could be the worst damages in a very bad solar flare, but a solar flare thats likely to happen in the next couple years with the solar maximum, like a really high x class, what could happen on earth? If nasa or noaa knew about this happening, would they tell everyone, if they would, what would we have to do to be safe from the flare, would they announce a national emergency?

    thank so much
  2. jcsd
  3. Jul 15, 2010 #2
    There are really two questions here. How much damage could a solar flare do on earth? Not much, most of the power lines are now protected, and use of short wave radio frequencies that will be most disrupted has been decreasing for decades.

    As for satellites, a big flare can puff up the thermosphere and cause them to deorbit early. However, during the recent quiet sun period, the opposite has happened, so it would average out.

    The other possibility though is called a coronal mass ejection (CME). These are associated with solar flares, and if an X class flare caused a CME headed toward Earth it could do a lot more damage to satellites (and humans) in orbit, to communications and to power distribution. Since the CME does not travel at the speed of light, it arrives at the Earth (if it is headed in that direction) one to five days after it leaves the sun.

    On 1 September 1859 there was a huge disruption in the Earth's magnetic field. This is thought to be the biggest CME to hit the Earth in recent history. Of course there was no radio, no television, no artificial satellites, and no long range electric transmission. So the only damage was to some telegraph cables.

    A CME of that size and speed (it arrived the same day as the associated flare) hitting the Earth today would be on the order of a billion dollars or so.

    If a large CME were to be detected approaching earth, the space station would be evacuated, which would be a significant fraction of the total cost. (The radiation would approach or exceed the LD50 dose for humans.) Putting astronauts in orbit is expensive, and some experiments on the space station would be ruined if left unsupervised--especially since there would probably be breakers blown, etc. on the space station.
  4. Jul 15, 2010 #3


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    Not much to humans directly, from what I understand. Had we been living over a couple hundred years ago, before the technological revolution, we probably wouldn't even notice.

    But in today's technological era, the outcome might be a little different, indirectly. If major electrical power outages and/or communications systems were disrupted, it could impact humans which have come to depend upon such systems.

    Here is a general solar flare Q/A from NASA's Dr. David P. Stern.

    And some related good news is that solar flares may now be easier to predict (and if if they are predicted, it follows that preventative action can be taken).
    http://www.noaanews.noaa.gov/stories2010/20100119_solarflare.html" [Broken]

    I don't know. But I would think so. They have a track record of being very forthcoming with estimates and warnings of disasters (warnings such as NOAA's report of impending disaster prior to hurricane Katrina striking New Orleans).

    But again, there's nothing really you'd have to do to be "safe from the flare." The flare itself won't harm you directly. But it wouldn't do any harm to have water, batteries, and canned food around.

    Here are a couple of links to estimates involving space weather and solar flares:

    Recent article from NASA:
    http://science.nasa.gov/science-news/science-at-nasa/2009/21jan_severespaceweather/" [Broken]

    A space weather FAQ from NOAA.
    http://www.swpc.noaa.gov/info/FAQ.html" [Broken]
    Last edited by a moderator: May 4, 2017
  5. Jul 16, 2010 #4


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    The fossil evidence shows no real evidence of CME or solar flare effects on life. Such an event now could, however, be inconvenient for cell phone users
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