Sunspot Variety
Summertime in Williamsburg, VA doesn't favor astronomical observing. Almost every day is cloudy. Rare cloudless observing windows last only a few morning hours before clouds pop up. One such unusual span of clear sky happened on the morning of July 11th. For a brief two hour period there were no clouds, no wind, and good seeing. Temperature was quite warm, but tolerable, ranging from 77 degrees to 81 degrees during my imaging session.
Solar activity is humming along nicely these days. The following 15-panel mosaic shows action on July 11th. Each individual panel is a stack of 100 frames from a 1,000 frame video clip made with a ZWO 174 MM camera, attached to a 3X Barlow lens on a Lunt 100 mm solar telescope.
One major sunspot, 3363, has a large umbra below center. From top to bottom on the right are sunspots 3361, 3367, and 3366. Sunspot 3372, with spiky eruptions, is emerging around the upper left rim. A few prominences are scattered around the limb. (Click on the images to see a larger view.)
The next 2-panel mosaic shows most of the features in the western hemisphere in good detail.
Sunspot 3361 is on top. Double umbra sunspot 3367 is in the middle. Sunspot 3366 is nearing the limb on the lower right accompanied by a nice prominence. Sunspot 3362, with a dim umbra, is in the lower left. Several filaments are scattered about making a nice solar scene.Moving to a portion of the eastern hemisphere, the following 5-panel mosaic shows big sunspot 3363 and prominences.
On the upper left rim you can see a "filaprom". This is a prominence in the process of rotating around to become a filament when viewed against the background solar disc. While observing I noticed the development of an interesting strand of light spanning the elongated umbras of sunspot 3363. The next two images show the change. At 8:50 EDT (12:50 UT) the umbra looked like this:
I've never seen an umbra eruption feature like this before!
Emerging sunspot 3372, just coming over the eastern limb, presented spiky, churning activity seen in profile.
Activity slowly changed in 25 minutes between 9:28 and 9:53 EDT. The next image, (slightly less sharp), shows the difference.Inevitable clouds began appearing around 10:40, and I was beginning to feel the summer heat. It was time to shut down and haul my equipment inside to wait for the next rare cloudless sky.