Moat flow

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GreatAttractor
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Moat flow

Post by GreatAttractor » Mon May 14, 2018 5:20 pm

I was checking arxiv.org today and if I'm not mistaken, the outflow around a sunspot's penumbra (granules spreading outward over a limited range from the penumbra), something I noticed back in 2012 in my WL animations, e.g. here:
Image
is probably what is called the moat flow. A sample paper: Correlations between sunspots and their moat flows. The horizontal velocity given (~1000 m/s) seems fitting ‒ over a few tens of minutes it would amount to a few thousand km, i.e. a few granule widths, more or less what the animation shows.

(Not to be confused with Evershed flow, which occurs in penumbra.)
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robert
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Re: Moat flow

Post by robert » Mon May 14, 2018 7:24 pm

Thanks fo this. Superb animation and interesting article
Robert
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Re: Moat flow

Post by marktownley » Tue May 15, 2018 5:12 am

Great animation and interesting stuff!
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Montana
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Re: Moat flow

Post by Montana » Tue May 15, 2018 11:39 am

Oh is that what it is called, I see that in all my WL animations too and the granulation cells are also slightly brighter than all the rest too, a bit like a halo round the spot.

Alexandra

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Carbon60
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Re: Moat flow

Post by Carbon60 » Tue May 15, 2018 7:26 pm

Very interesting. Thanks for that.

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