APOD: Bright Points on the Quiet Sun (2010 Apr 16)

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Expand view Topic review: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

Re: magnetic cyclones?

by neufer » Fri Apr 16, 2010 7:04 pm

Beta wrote:Can someone point me to a more rigorous explanation of the dynamics involved here?

The area of the rising columns is much greater than the area of the descending walls, so even accounting for the cooler plasma being denser, it must be traveling much faster. The bright pinholes occur only in the cooler (faster) regions... Why? The magnetic tubes (or whatever) must have some interaction with the plasma, so that as they wander around they tend to move into regions that are {cooler|faster|moving down, not up}. Which one(s), and why?
You'll find the answer in here
(assuming that you can lift the book):
Image

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by Chris Peterson » Fri Apr 16, 2010 5:57 pm

Pierre Dufresne wrote:It looks an awful lot like numerical wrap-around to me (as in, subtract 1 from a (unsigned short integer) zero on a computer and you get +65536 instead of -1 ). Symptom? The edges between the bright points and the dark background looks too sharp compared to the rest of the image. I've written my share of buggy image processors, so I've seen stuff like this before.
I think we can be confident that this isn't happening here, however. The effect shows up in different images processed in different ways. It is also pretty clear from the image description that this has been studied closely, meaning that the underlying data has been analyzed (e.g. photometrically) and that this isn't simply a processing artifact.

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by Pierre Dufresne » Fri Apr 16, 2010 5:34 pm

It looks an awful lot like numerical wrap-around to me (as in, subtract 1 from a (unsigned short integer) zero on a computer and you get +65536 instead of -1 ). Symptom? The edges between the bright points and the dark background looks too sharp compared to the rest of the image. I've written my share of buggy image processors, so I've seen stuff like this before.

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by neufer » Fri Apr 16, 2010 5:12 pm

gingerd wrote:I think we have the first published picture of Hell! If you examine the granules closely you can discern
many tortured human faces a la Hieronymus Bosch. I often wondered where the bad ones went!
Image

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by neufer » Fri Apr 16, 2010 5:06 pm

biddie67 wrote:Those bright spots are like windows into the soul of the sun.
The sole soul of Sol?

magnetic cyclones?

by Beta » Fri Apr 16, 2010 3:42 pm

Can someone point me to a more rigorous explanation of the dynamics involved here?

The area of the rising columns is much greater than the area of the descending walls, so even accounting for the cooler plasma being denser, it must be traveling much faster. The bright pinholes occur only in the cooler (faster) regions... Why? The magnetic tubes (or whatever) must have some interaction with the plasma, so that as they wander around they tend to move into regions that are {cooler|faster|moving down, not up}. Which one(s), and why?

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by gingerd » Fri Apr 16, 2010 2:04 pm

I think we have the first published picture of Hell! If you examine the granules closely you can discern many tortured human faces a la Hieronymus Bosch. I often wondered where the bad ones went!

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by biddie67 » Fri Apr 16, 2010 1:17 pm

emc wrote:What is up besides the Sun? I am so discombobulated. In my head, I know that the Sun is not rising or setting… or up and down... but is plowing through the Local Interstellar dust cloud, orbiting the Milky Way at about 486,000 miles per hour… And the Earth is rotating causing the day and night… I know this, but my head keeps moving the Sun up, across the sky and down again… day after day. It is as if my genetic code has embedded this into my brain. Is there no hope?
I'm with emc - sometimes it's so hard to keep hold of the "big picture" when the only picture I see moves the same way overhead each day - a real ying-yang internal fight .....

============

Those bright spots are like windows into the soul of the sun.

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by owlice » Fri Apr 16, 2010 12:57 pm

:: hands Astronut a cuppa ::

Monarch butterflies for me. Not to drink (oog, neufer, what an idea! What WAS Mrs. Olson thinking?!) -- ultra dark French roast this AM -- but for what the image brings to mind.

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by Astronut » Fri Apr 16, 2010 12:53 pm

Oh, tip toe thru the tulips - thru the tulips - thats all i see - Oh tip toe thru the tulips with me-e-e-e-e-e-e.

Sorry, i just got up.

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by neufer » Fri Apr 16, 2010 12:14 pm

Wackybaby wrote:Butterflies?
Looks like slightly magnified coffee grains to me. :)
Which reminds me...
Swedish legend Mrs. Olson, has secretly replaced the fine coffee that "Wackybaby" usually
drinks in the morning with Monarch butterflies. Let's see if she can tell the difference!
  • Image

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by neufer » Fri Apr 16, 2010 12:05 pm

emc wrote: Is there no hope?
Kibo (きぼう, Hope), is a Japanese science module on the International Space Station (ISS).

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by Wackybaby » Fri Apr 16, 2010 12:02 pm

Butterflies?
Looks like slightly magnified coffee grains to me. :)
Which reminds me...

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by emc » Fri Apr 16, 2010 11:13 am

Image
What is up besides the Sun? I am so discombobulated. In my head, I know that the Sun is not rising or setting… or up and down... but is plowing through the Local Interstellar dust cloud, orbiting the Milky Way at about 486,000 miles per hour… And the Earth is rotating causing the day and night… I know this, but my head keeps moving the Sun up, across the sky and down again… day after day. It is as if my genetic code has embedded this into my brain. Is there no hope?

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by neufer » Fri Apr 16, 2010 10:37 am

rstevenson wrote:I think North America is just a tad wider than 1000 km. Roughly 8 times wider, most days.
There is a Swedish legend that claims it to be roughly 7000 km. wide. :wink:
  • Legend, n. [OE. legende, OF. legende, F. légende, LL. legenda, fr. L. legendus to be read, fr. legere to read, gather; akin to Gr. to gather, speak. Cf. Collect, Dialogue, Lesson, Logic.]

    1. A nonhistorical or unverifiable story handed down by tradition from Earlier times and popularly accepted as historical.

    4. A table on a map, chart, or the like, listing and explaining the symbols used.

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by dduggan47 » Fri Apr 16, 2010 9:52 am

Wow. This one blows me away. Great picture.

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by rstevenson » Fri Apr 16, 2010 9:19 am

neufer wrote:Image
I think North America is just a tad wider than 1000 km. Roughly 8 times wider, most days.

Rob

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by Erik B » Fri Apr 16, 2010 7:48 am

This picture looks like the bright spots are maybe where the descending plasma is making contact with the lower surfaces. Which might be why its visible.

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by neufer » Fri Apr 16, 2010 4:31 am

GeOgre wrote:Reminiscent of a flock of monarch butterflies!
ImageImage

Re: APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by GeOgre » Fri Apr 16, 2010 4:22 am

Reminiscent of a flock of monarch butterflies!

APOD: Bright Points on the Quiet Sun (2010 Apr 16)

by APOD Robot » Fri Apr 16, 2010 4:04 am

Image Bright Points on the Quiet Sun

Explanation: Up close, the solar surface is a striking patch work of granules in this very high resolution picture of the quiet Sun. Caused by convection, the granules are hot, rising columns of plasma edged by dark lanes of cooler, descending plasma. But the high-resolution view reveals that the dark lanes are dotted with many small, contrasting bright points. Constantly present on the solar surface, the bright points do not seem to be related to sunspots that come and go with the magnetic solar cycle. Nonetheless, the bright points are regions of concentrated magnetic fields and are bright because the magnetic pressure opens a window to hotter deeper layers below the photosphere. For scale, the white bar at the lower left corresponds to 5,000 kilometers across the Sun's surface. The sharp, narrow-band image was recorded in September, 2007 using the Swedish Solar Telescope on the astronomical island of La Palma.

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