APOD: Sunspot Group AR 2339 Crosses the Sun (2015 Jun 29)

[APOD Robot]

Sunspot Group AR 2339 Crosses the Sun

Explanation: How do sunspots evolve? Large dark sunspots -- and the active regions that contain them -- may last for weeks, but all during that time they are constantly changing. Such variations were particularly apparent a few weeks ago as the active region AR 2339 came around the limb of the Sun and was tracked for the next 12 days by NASA's Solar Dynamic Observatory. In the featured time lapse video, some sunspots drift apart, while others merge. All the while, the dark central umbral regions shift internally and their surrounding lighter penumbras shimmer and wave. The surrounding Sun appears to flicker as the carpet of yellow granules come and go on the time scale of hours. In general, sunspots are relatively cool regions where the local magnetic field pokes through the Sun's surface and inhibits heating. Over the past week, an even more active region -- AR 2371 -- has been crossing the Sun and releasing powerful flares that have resulted in impressive auroras here on Earth.

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[Beyond]

Reminds me of some rusty areas on a truck i once had.

[madtom1999]

Is it my imagination or are sunspots ever so slightly lower than the rest of the surface of the sun?

[Boomer12k]

Awesome video...
OK...we are in Solar Maximum, and it is really showing here in the North West. We generally have a wet May, and can even have a wet June...both have been very dry...especially June, and we are headed for 103 F degree weather by Thursday.

SO.....how come so hot, and heating of the Sun....when Sunspots are inhibiting heat, and are cooler regions and there are MORE OF THEM???? Seems counter intuitive...

Reminds me of the "simulation" of LIFE...on the old Computers, like the C64...pixels move around an gobble and cancel out others, while others are created, a move across the screen.

:---[===] *

[hoohaw]

Yawn! Vieux jeu! Déja vu! Galileo did it better: http://galileo.rice.edu/sci/observation ... wings.html

[Joules]

Looks like it left the front of the sun in late middle age, before all the little spotlets start to disappear.
Did 2339 make it around for a renumbered, second trip across the front face?
Beautiful animation. APOD would do well to post a few more like this, as they don't all evolve the same way.
Wierd solar max this time around: http://www.sidc.be/silso/yearlyssnplot

[emc]

I think this Sun spot thing could be used as an example for why we don't necessarily need to be so concerned about the tidiness of our homes. And if you also consider the amount of dirt resident on our home planet... well, it seems our cosmic environment is telling us that to be normal, we don't need to be so worried about dusting our mantles.

[Chris Peterson]

OK...we are in Solar Maximum, and it is really showing here in the North West. We generally have a wet May, and can even have a wet June...both have been very dry...especially June, and we are headed for 103 F degree weather by Thursday.

SO.....how come so hot, and heating of the Sun....when Sunspots are inhibiting heat, and are cooler regions and there are MORE OF THEM???? :shock: Seems counter intuitive...

The impact of sunspots and solar activity on the amount of solar radiation we receive from the Sun is minimal. We can see subtle climatic variation correlated with the solar cycle, but no discernible impact on weather at all. And what impact there is might well be counterintuitive. Secondary effects of solar cycle, such as the variation in charged particle flux, alter our upper atmosphere and therefore our climate. Those effects are stronger than the effects of tiny differences in total solar radiation.

[Dad is watching]

Reminds me of the "simulation" of LIFE...on the old Computers, like the C64...pixels move around an gobble and cancel out others, while others are created, a move across the screen.
:---[===] *

My Dad said the same thing, and then had to explain what the 'Game of Life' was. So ancient...

We had a question about sunspots tho. We understand that they form because of deviations in the magnetic field of the sun. Do these deviations originate in the core or is there some intervening substance (metallic hydrogen, etc) between the core and the surface that cause the magnetic field to fluctuate? Or are the magnetic fields generated in local proximity to the sun spot much closer to the surface (again by something like metallic hydrogen)?

[Chris Peterson]

We had a question about sunspots tho. We understand that they form because of deviations in the magnetic field of the sun. Do these deviations originate in the core or is there some intervening substance (metallic hydrogen, etc) between the core and the surface that cause the magnetic field to fluctuate? Or are the magnetic fields generated in local proximity to the sun spot much closer to the surface (again by something like metallic hydrogen)?

The Sun's magnetic field is created by a dynamo process- the bulk movement of conductive fluid throughout the interior. Convection and other processes create non-uniformities in the field, which in turn results in sunspots at the surface.

That's a very general explanation. There's a lot we don't know about stellar magnetic fields, and a lot of gruesome details in what we do know.

[Ron-Astro Pharmacist]

Gruesome details. Now that sounds intriguing Chris. When larger space telescopes or other improved technology comes into being, should our knowledge of starspots and other star's magnetic fields vastly improve? Considering the difficulty of currently detecting precise details, it begs the question on how much we can we extrapolate onto all the other varieties of stars from our current understanding of our sun's spots based on the measurement of our sun's own magnetic underpinnings?

As far as the "gruesome details" I suspect you mean the details of electricity and magnetism that takes years to learn thus difficult to go into in a short explanation. Indeed a good reason to learn them early in one's education.

[DavidLeodis]

The explanation refers to the SDO as the 'Solar Dynamic Observatory' but the SDO website calls it the 'Solar Dynamics Observatory'. I appreciate that the slight difference may be of no significance and is probably just a clerical error but I thought I would mention it.