Author Topic: Black Sphere near sun explanation?  (Read 6674 times)


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Black Sphere near sun explanation?
« on: September 21, 2012, 09:06:59 am »
I must making uncomfortable to some, I'd say by the lack of the posts with the keywords "black sphere sun".

I can't believe nobody asked that in this website, so I have to think it's purposely not indexed, removed, buried, ignored??

Anyway, can any scientist explain this?

…or… if you already did, can you provide a link to it?… and please make sure it's find-able?



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Re: Black Sphere near sun explanation?
« Reply #1 on: September 21, 2012, 04:30:35 pm »
I'd have to say that the most likely reason there isn't a discussion around that event here is that similar events are pretty common, and as well understood as most solar phenomenon. 

To clarify, the dark region there is what's known as a 'polar crown cavity' or 'coronal prominence cavity,' and they form one of the main parts of a Coronal Mass Ejection when they erupt.  The general shape of these cavities is 'U' shaped, and if you look at your video, you'll notice there isn't actually a sphere, just an arc, our brains are excellent at filling in the gaps.  Actually, there's another one just north of it on the edge of the sun that is more V shaped.

What makes this particular cavity especially eye catching is that there's no other coronal structures behind or in front of it, making the cavity especially clear to see.  This is largely because it belongs to a prominence(that dark line 'connecting' it to the sun) that stretched across a large portion of the suns surface.  March of this year is very recent in terms of scientific papers so there isn't anything about this particular event published yet, but I imagine this lovely cavity will be the object of discussion for a paper or two because we have such a clear, unimpeded view of it. 

If you'd like to read more about the subject there's a recent paper on an event from June 2010 that goes through the mechanics of what they are, how they form, and why they're the shape they are.


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Re: Black Sphere near sun explanation?
« Reply #2 on: October 11, 2014, 10:44:48 am »
Excellent. I like you comment. It good to do that