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Post by THEO BAKALEXIS on Jan 22, 2011 17:27:23 GMT
Fair-medium seeing today from athens. The only magnetic activity at the North of the disk. There we have two active region with sunspots, two Q.R.Filaments and one great promonence at west. www.solar-007.eu/
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Post by af4ex on Jan 22, 2011 21:51:52 GMT
@theo, > There we have two active region with sunspots, two > Q.R.Filaments and one great promonence at west. This is great work. The Hydrogen and Calcium filters are showing the areas of magnetic activity around the spots, which means these ions, especially Calcium, must be sensitive to magnetic effects. I traced the outline of the two regions, Hydrogen (center) Calcium (right) The prominence (left), in Hydrogen, on the west limb is very stunning. Attachments:
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Post by af4ex on Jan 23, 2011 16:30:05 GMT
I've been watching the old 1141 ("[1141]") region for awhile. A few days ago we could see its magnetic coronal loops from the far side and it looked bright in the STEREO 195A light. But now that it has rotated into view, it has turned out to be disappointingly dim in most wavelengths. Still bright in SDO 193A, but almost invisible in x-ray and continuum. Not likely to show any spots so I don't expect this region to be officially recognized by NOAA/USAF. (But I hope I'm wrong.) Attachments:
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Post by af4ex on Jan 23, 2011 16:48:09 GMT
... more "promising" (for those of us longing for more solar activity) is the far side area. Old 1133/1140, record holder for SC24's 'largest sunspot' still seems to be going strong. And in the south, a large filament cavity has persisted for several months, site of the 'monster filament' of 5 Dec that Theo captured in Athens. Also site of former 1112/1121 which produced numerous C- and even a few M-class flares. Surprising how this area seems to persist over the past few months. Perhaps this is the region where the long-awaited 'spike' will occur that will shoot the SC24 SFI above 100 for the first time. Seems likely to occur soon (based on historical extrapolations). FYI, some more information on filament cavities and how they manage to persist (from Wikipedia): en.wikipedia.org/wiki/CoronaFilament cavities Filament cavities are zones which look dark in the X-rays and are above the regions where Há filaments are observed in the chromosphere. They were first observed in the two 1970 rocket flights which also detected coronal holes.[9]
Filament cavities are cooler clouds of gases suspended above the Sun's surface by magnetic forces. The regions of intense magnetic field look dark in the images, because they are empty of hot plasma. In fact, the sum of the magnetic pressure and plasma pressure must be constant everywhere on the heliosphere in order to have an equilibrium configuration: where the magnetic field is higher, the plasma must be cooler or less dense. The plasma pressure p can be calcutated by the state equation of a perfect gas p = nKBT, where n is the particle number density, KB the Boltzman constant and T the plasma temperature. It is evident from the equation that the plasma pressure lowers when the plasma temperature decreases respect to the surrounding regions or when the zone of intense magnetic field empties. The same physical effect makes sunspots dark in the photosphere.
A large coronal hole is also starting to rotate into view and should deliver some faster solar winds to stir up the geomagnetism here on Earth, perhaps a week or so from now. Attachments:
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Post by af4ex on Jan 25, 2011 17:05:03 GMT
While waiting for those far-side regions to rotate into view, I am noticing something odd about the STEREO Panorama (below left). I assume the "zero" longitude is directly facing Earth, so the edges of visibility should be +90 and -90 degrees longitude, right? STEREO shows that some pieces of the coronal hole and filament cavity have already rotated Earthside. But looking at the SDO AIA image of approximately the same time, I don't see these items (yellow circles). Is this because they're buried in the chromosphere, so invisible when viewed obtusely? Or are the longitude markings off somehow? Can anyone explain what's going on here? Thanks, John/af4ex Attachments:
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Post by af4ex on Jan 26, 2011 1:33:19 GMT
... those "missing" regions (coronal hole and filament cavity) have finally started to show up in the latest ADO AIA 171A, timestamped 0021Z, about 7 hours after the STEREO timestamp. I don't think the longitude markings on the STEREO panorama are correct. In any case, solar activity should start picking up in a day or so as all that old activity starts marching in (again). Attachments:
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bradk
Level 3 Rank
Posts: 199
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Post by bradk on Jan 26, 2011 2:16:35 GMT
Nice catch John.
Time will tell if it the same old increase as last rotation, or actually an increase over the last increase.
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Post by af4ex on Jan 26, 2011 4:39:21 GMT
Observed a strange-looking dark column rising out of the old filament cavity region on the southeast limb. Very tall, rising into the corona. Perhaps some kind of "super spicule"? Probably not, because it's much cooler than the surroundings. SDO/AIA 171A 2011-01-26 03:49:37 UT Attachments:
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Post by af4ex on Jan 26, 2011 11:36:07 GMT
It's still there. Shows up better in 304A light. Just a big filament. :-| Attachments:
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Post by af4ex on Jan 26, 2011 14:03:30 GMT
Neat find in any case. Are we going to go back to zero sunspots in a day or two or will a speck appear? Old 1141 is still magnetically active and might pop out in spots (but it's weak in x-ray and microwaves, so low probs on that) But our best hope is the "new" filament cavity region, with several active-looking regions which should start rotating into view soon. Take a look at this same region on 5 Dec (two rotations ago!), a huge filament not so different from the one that's there right now: :-] Attachments:
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Post by af4ex on Jan 26, 2011 16:28:32 GMT
I guess I'm just starting to recognize filaments. Seems to be another huge one jumping out near old 1141 and disappearing over the NorthEast limb. (But probably not as big as the one in the SouthEast ) [Maybe Theo will catch these filaments in hydrogen and calcium light] Attachments:
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Post by af4ex on Jan 27, 2011 5:03:52 GMT
A middle-sized B-class x-ray flare was reported a short while ago in the vicinity of 1149. Perhaps the last before it rotates off to the far side. Also noted flaring from the newly arriving filament cavity region (II) on the east limb, a good sign. And another flaring from a tiny hotspot (I) which just sprouted, but is visible in both microwave and x-ray. So it might develop some spots and get promoted to Active Region. Overall activity is slightly declining, judging from 10.7 cm radio flux, which is back down to 80. But I expect it to rise soon as the far side activity rotates into view: 2011 Jan 12 2800 80 80 80 2011 Jan 13 2800 80 80 79 2011 Jan 14 2800 80 79 79 2011 Jan 15 2800 81 80 81 2011 Jan 16 2800 81 80 80 2011 Jan 17 2800 81 82 82 2011 Jan 18 2800 83 81 81 2011 Jan 19 2800 81 81 81 2011 Jan 20 2800 83 82 82 2011 Jan 21 2800 87 88 87 2011 Jan 22 2800 88 88 87 2011 Jan 23 2800 86 84 84 2011 Jan 24 2800 82 83 82 2011 Jan 25 2800 82 81 81 2011 Jan 26 2800 80 80 80 Attachments:
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Post by af4ex on Jan 27, 2011 12:00:01 GMT
I said: > So it might develop some spots and get > promoted to Active Region. Ok, I can see some specks. But are they big enough to be seen in Wolf's 80mm telescope? :-\ Attachments:
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Post by vk2fdxr on Jan 28, 2011 1:09:01 GMT
M-Class Flare!
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Post by af4ex on Jan 28, 2011 1:58:41 GMT
> M-Class flare. Yes, there is a spectacular view of it (below) on the Nobeyama radioheliograph right now. It came from 1149, which seems to be over the on the far side now, but blew off a big CME which you can see here in motion: solar.nro.nao.ac.jp/norh/html/10mins/2011/01/28/movie.htmlSimultaneously, there was a B or C flare from the opposite limb at the newly emerging region, which is also showing some spots and a huge filament leaping to the far side. The Sun appears to be burning its candle at both ends! That's a good sign, maybe time for a big spike in activity. Attachments:
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