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Difference between flare, CME and SPEs

  1. Jan 26, 2005 #1
    I read that coronal mass ejections and flares are independent things that can cause solar particle events. The particles emitted by the first travels at about 1,000km/s and can reach us in days, while the particles emitted by the last travels at near light speed and can reach us in minutes. Besides that, as I noticed that the most dangerous SPEs are often associated with flares, I suppose CMEs offer smaller radiation doses in average.

    And according with what I read, I suppose that the X-ray emission of the flare is not a concern for someone in deep space, when compared with the SPE it can produce. I would like to confirm those things.

    I have found great information about equivalent doses for galactic cosmic rays and some major SPEs of the past, but info on internet is somewhat oversimplified when the matter is to tell the differences between flares, CMEs, SPEs, and the risk each one offers to someone in deep space, considering their strength and likeliness to happen.

  2. jcsd
  3. Feb 6, 2005 #2
    You should try to define what you mean by "deep space". Of course the X-ray content of very strong flares would be damaging to a person in Earth if that person wouldn't be protected by Earth's athmosphere. In fact, communication satellites are damaged when a malign flare occurs. But the X-ray content of solar flares will not affect to a person "in deep space" if "deep space" means for example, a comoving radial distance of 20 Gly

    The strongest solar flare ever recorded was rated as X28, and ocurred in 2003

    Neutron stars can also produce flares. Neutron star flares are now candidates to mini GRBs
    Last edited: Feb 6, 2005
  4. Feb 13, 2005 #3
    By deep space I mean outside Van Allen belts.

    I would like to add one more question: I have heard about the Helen Dodson Prince classification for flares,

    http://ngdc.noaa.gov/stp/SOLAR/ftpsolarflares.html#cfi [Broken]
    (botton of the page)

    wich can range from 1 to 17. It takes several new features in account if compared with the usual 1-8A W/m2 flux. I´m interested in flares wich might be dangerous to astronauts. Is that classification a good one for that matter? What would be a "malign flare" in that scale?
    Last edited by a moderator: May 1, 2017
  5. Mar 8, 2005 #4
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