NASA’s Dr. David Hathaway has just published a new paper, and it has advanced solar science. He’s found something they’ve been looking for a long time; long lived convection cells. Massive, long-lasting plasma flows 15 times the diameter of Earth transport heat from the sun’s depths to its surface, according to a study in the Dec. 6 Science. The finding supports a decades-old explanation of why the sun rotates fastest at its equator.
Convection motions within the Sun transport heat from its interior to its surface. The hot regions are seen as granular (∼1000 kilometers across) and supergranular (∼30,000 kilometers across) cells in the Sun. Using data from the Helioseismic Magnetic Imager on the Solar Dynamics Observatory, Hathaway et al. (p. 1217) found evidence for even larger cells that have long been predicted by theory but not unambiguously detected. The flows associated with these giant cells transport angular momentum toward the equator and are important for maintaining the Sun’s equatorial rotation.
Video follows:
GO WITH THE FLOW Long-lasting plasma flows appear in red and blue in this animation, which portrays data from four solar rotations. Some flows persist for several months; these patterns are especially visible near the sun’s north pole. Scientists think these flows keep the sun’s equator rotating faster than its poles.
The paper:
Giant Convection Cells Found on the Sun
1NASA Marshall Space Flight Center, Huntsville, AL 35812, USA.
2Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235, USA.
3Department of Space Science, University of Alabama in Huntsville, Huntsville, AL 35899, USA.
4Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627, USA.
Heat is transported through the outermost 30% of the Sun’s interior by overturning convective motions. These motions are evident at the Sun’s surface in the form of two characteristic cellular structures: granules and supergranules (~1000 and ~30,000 kilometers across, respectively). The existence of much larger cells has been suggested by both theory and observation for more than 45 years. We found evidence for giant cellular flows that persist for months by tracking the motions of supergranules. As expected from the effects of the Sun’s rotation, the flows in these cells are clockwise around high pressure in the north and counterclockwise in the south and transport angular momentum toward the equator, maintaining the Sun’s rapid equatorial rotation.
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vukcevic says:
December 6, 2013 at 9:42 am
I put these 3 images together (MDI con, Solar cells & magnetogram)
http://www.vukcevic.talktalk.net/sun.htm
Regrettably, visually I can’t see any great relevance to the formation of sunspots or magnetic field distribution, hopefully Hathaway & co may find and explain the link if there is one (surely must be one lurking in the undergrowth)
———–
You must of forgot about SDO imagery.
From the link, input for start/end date 2010-06-08, then chose imagery type 193, from the drop down menu. The N/S angle is a little N ward in the convection construction image from our article above, but I think you might see some of the flows in the imagery from SDO…
http://iris.lmsal.com/iristoday/
Note link is for the new “IRIS” eye on the sun, but has the SDO also. There will be a presentation at AGU for IRIS.
If Dr. S. is still around here somewhere. When you started your sectors watch 46 years ago, I was only 10. Good precursor for anyone might be some of your earlier articles on sectors and boundaries. Told myself in around 09 that I would have to read sectors and boundaries again. And now we have, “FLARING SOLAR HALE SECTOR BOUNDARIES,” along with the even newer, convection cells, complete with models.
http://www.leif.org/research/Hale-Flares.pdf
Is there a cycle dependency, in timing or strength, on whether there will be 2 or 4 warps in the heliocurrent sheet? It is wavey er during lower solar cycles because..
Carla says:
December 8, 2013 at 8:15 am
Is there a cycle dependency, in timing or strength, on whether there will be 2 or 4 warps in the heliocurrent sheet? It is wavey er during lower solar cycles because..
Check out: http://www.leif.org/research/Solar%20Sector%20Structure.pdf and
http://www.leif.org/research/Long-term%20Evolution%20of%20Solar%20Sector%20Structure.pdf
Some might use slightly different terminology but this seems relative to sectors and boundaries and cells of convective flows..
Distribution of flares on the sun-Superactive regions and active zones of 1980-1985
T Bai – The Astrophysical Journal, 1987 – adsabs.harvard.edu
Distribution of flares on the sun during 1955-1985-‘Hot spots'(active zones) lasting for 30 years
T Bai – The Astrophysical Journal, 1988 – adsabs.harvard.edu
The north-south distribution of major solar flare events, sunspot magnetic classes and sunspot areas (1955–1974)
JR Roy – Solar Physics, 1977 – Springer
so if we are looking for a consistency in these convective flows for years…
Carla says:
December 8, 2013 at 9:32 am
Some might use slightly different terminology but this seems relative to sectors and boundaries and cells of convective flows..
Yes, those ‘active longitudes’ have been recognized for more than a hundred years. Maunder was the first to draw attention to them.
And Vuks,
Try, 2010-06-08 with 211_193_171 from the drop down menu, on the link..
http://iris.lmsal.com/iristoday/
Thanks Dr. S…have fun…
Yes, thanks Dr. S., this does answer some of my questions and creates more. lol But, is there more of an inward component than an outward. That the inward component of the structures is more dominant?
Long Term Evolution of the Solar Sector Structure
http://www.leif.org/research/Long-term%20Evolution%20of%20Solar%20Sector%20Structure.pdf
Svalgaard and Wilcox 1974
… During most of the cycle a four-sector structure with asynodic recurrence period near 27 days is apparent. On the other hand, near sunspot maximum a superposed structure having polarity into the Sun and width in longitude of about 100 deg. and a recurrence period between 28 and 29 days can be observed. This 28 1/2 day feature co-exists with the underlying basic four sectors for several years. It may at these times be more difficult to discern the four-sector structure clearly, and the observed solar -structure has in a first approximation only two sectors per rotation. But when the 28 1/2 day structure weakens sometime after sunspot maximum, the four-sector pattern becomes very prominent again as the cycle progresses towards sunspot minimum. …
So more wavy current sheet during minimum and/or reduced (low activity) solar cycle?
Now this is pretty significant and interesting..for our understanding of these convective cells too..
Long Term Evolution of the Solar Sector Structure
http://www.leif.org/research/Long-term%20Evolution%20of%20Solar%20Sector%20Structure.pdf
Svalgaard and Wilcox 1974
… In this paper we present evidence for the notion that the basic four-sector structure is a manifestation of a intrinsic three-dimensional structure in the global solar magnetic and/or velocity fields.
The structure is a very long-lived and appears to have existed throughout the last five sunspot cycles, and by implication probably much longer than that.
It will be shown that the sector boundaries drift slowly in longitude. These slow systematic longitude drifts are related to the sunspot cycle in the sense that from sunspot minimum until the polar fields reverse shortly after the maximum, the sectors drift westwards. After the polar field reversal, the sectors drift eastward until the next minimum, when they again resume a westward drift. The drifts are slow, of the of 20 deg. of longitude per year…
Might that structure be a birth mark of sorts?
The drift reminds me, Earth’s wavy magnetic equator has a drift. As well as other drifts within the region..
Figure 5 expands brain and head explodes..wowee
“the existence of a negative polarity feature with a 28 1/2 day recurrence period” and kaboom
But the galactic mother brain says, your looking at Figure 5 from the wrong Earthly angle again.
Long Term Evolution of the Solar Sector Structure
http://www.leif.org/research/Long-term%20Evolution%20of%20Solar%20Sector%20Structure.pdf
Svalgaard and Wilcox 1974
…Figure 5 shows in a compact representation the three principal features that emerge from the present analysis: (i) a persistent four-sector structure which may be followed from one cycle to the next and presumabley represents a very long-lived structure in solar magnetic fields, (ii) systematic changes of the recurrence period – or rotation period – of this four-sector structure: faster rotation in the first half of a sunspot cycle, slower rotation in the last half, and
(iii) the existence of a negative polarity feature with a 28 1/2 day recurrence period; the 28 1/2 day structure seems to be most prominent near sunspot maximum, although at times can be quite distinct even near minimum such as in 1943 and in 1972-73…
Good stuff, now maybe a lookee see at “FLARING SOLAR HALE SECTOR BOUNDARIES.”
This all does sorta remind me of the “Arctic Oscillation.” (Polar Oscillation)
Sometimes, in Negative phase (high pressure) and more wavy the jet stream.
Then at other times Positive phase (low pressure) more flat or smooth the jet stream.
Sure hope some members of the IRIS mission have a working understanding of:
Long Term Evolution of the Solar Sector Structure
http://www.leif.org/research/Long-term%20Evolution%20of%20Solar%20Sector%20Structure.pdf
Svalgaard and Wilcox 1974
AGU 2013
FM13 First Results from the Interface Region Imaging Spectrograph IRIS Mission PressConference
Should have been video 21 on the playlist.