Oh, snap! Another X-class flare from the Sun

By Phil Plait | October 23, 2012 11:59 am

Yesterday, an active region on the sun – basically, a collection of magnetically active sunspots – popped off a series of flares that were actually fairly energetic. NASA’s Solar Dynamics Observatory caught the action in this video:

Neat! These shots were in the ultraviolet, where flares are easier to spot.

Sunspots are where the Sun’s complex magnetic field pokes through the surface. The field lines store ridiculous amounts of energy (did you see my BAFact for today?), and allow plasma – superheated, ionized gas – to flow along them. Think of these field lines like a pillowcase full of tightly wound springs. If one of them snaps – which can happen if they get too close to each other, for example, or when the churning surface of the Sun ratchets up the tension in the field lines beyond their capacity to restrain themselves – it blasts out its energy, which then snaps other lines, which release their energy, and so on. You get a cascade of explosions, resulting in a solar flare.

Flares can be pretty small, or hugely huge. Scientists categorize them by the amount of X-ray energy released, so we have low-energy C class, medium M class, and yikesingly X class. This flare from yesterday just edged into X class territory, so it was decent, but not too bad. Happily it was on the edge of the Sun, and the blast was directed away from Earth, so it’s not expected to affect us. For further reassurance, there have been 14 previous flares since this new sunspot cycle began a couple of years ago, and we’re still here.

However, as the Sun spins, this active region is rotating toward us. If it stays active, we could see some interesting events from it that can cause aurorae on Earth. The odds of anything bad happening – power outages, or loss of satellites, for example – are low, but not entirely zero. I personally am not too worried about it, but it’s always good to keep our eyes on our nearest star. It can pack quite a punch, and we’re still a year or so away from the peak of the current sunspot cycle.

Image credit: NASA/SDO

Related Posts:

The Sun unleashes an X5.4 class flare
Awesome X2-class solar flare caught by SDO
NASA’s guide to solar flares
The August solar eruption, in HD video!


Comments (6)

  1. ErisWolf

    Once again, 1st class awesome from Phil Plait!

  2. Zenzan

    “The odds of anything bad happening – power outages, or loss of satellites, for example – are low, but not entirely zero. I personally am not too worried about it …. ”

    Lucky you are not an Italian earthquake scientist, Phil. With that sort of statement, if the sun goes bang on the Mayan Doomsday day date then you may get to share a cell with a rather large bloke named ‘Mutha’.

    Joking, Phil – I know it’s a beat up (though you should do a death from above talk on that day :)) but it is unbelievable they locked up those Italians 

  3. Seven days form now in good opposition: an X-5 flare, a huge CME, and ISS FUBAR personnel are radiation sick puking up their GI linings. The greatest obstacle to understanding reality is not ignorance but the illusion of knowledge. Reality is not a peer vote. NASA propaganda holds a vast audience diligently converting glitter into a tyranny of immersive falsehoods.

  4. DanM

    …and randomly generated words strung side by side do not profundity make.

  5. Rob

    Holy crap. And i believe that if you look close enough, you can see resonance waves on the surface surrounding the flare…. Though that could be an effect of the camera.

  6. Wzrd1

    @DanM, thanks. I got lost at ISS FUBAR and couldn’t even FIND that rabbit hole.


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