2012 May 12th and 13th – NOAAs 11476, 11477, 11478, 11479

Equipment used: Celestron 102 XLT, LXD75, Baader Planetarium Hyperion 8-24mm Mark III, Thousand Oaks glass white light filter

2012 05 12, 1315 UT – 1440 UT
Temp: 18.8°C, winds N 10 mph, scattered to 75% overcast, 78% H
Seeing: Wilson 4, Transparency: 5/6, 125x, Alt: 22.3, Az: 081.2

2012 05 13, 1330 UT – 1530 UT
Temp: 21.1°C, winds NNW 7 mph, clear to scattered, 88% H
Seeing: Wilson 4, Transparency: 5/6, 125x, Alt: 41.7, Az: 091.8

Sketches created at the eyepiece with WH Smith white cartridge paper (135 gsm), felt-tipped black artist pen, charcoal pencil, black oil-based pencil and then flipped and rotated to match standard orientation.

1476 continues to put on a show each day. Seeing appeared to be fairly good but when I increased magnification for a close up view of that active region on both days, I struggled to get clear enough definition within it to do a close up sketch (although I made several starts which ended up crumpled to the ground next to my observing chair.) The intricate patchwork of penumbrae was a blast to sketch, not to mention observing the numerous speckles of umbrae within that region. My hat is off to all solar sketchers that were able to capture the scene so well as a close up. It certainly is not an easy region to render, but so worth the effort for an in-depth study. I could easily get lost in that region for hours! The few sunspots that lead to the east out of that region look as if they are trying to grasp at the very last following sunspot to reel it begrudgingly back in.

Seeing was perfect for full disk sketching and lowering magnification to 50-70x really brought out the contrast for plage. Three spots were seen both days in active region 1479. On the 12th, it was easily noticeable how they appeared closer together when nearer to the edge of the limb along with a foreshortening called Wilson’s effect. Penumbrae were observed in the two preceding sunspots with perhaps slight penumbra in the third following spot in that grouping. Faculae surrounded the two following spots and there were lines of facula on either side of the preceding larger spot. On the 13th, the following sunspot was little softer indicating a very faint line of penumbra while the two preceding sunspots showed very definite penumbra, although still a little flattened by foreshortening. The middle sunspot in that group appeared to have a separated umbra, verified later today by the SDO’s continuum image.

There was only one sunspot both days within each active region 1477 and 1478 with umbra and penumbra. They appeared slightly larger than the spots in 1479.

There were quite a bit of faculae on the eastern limb with a small sunspot observed both days. The sunspot had both umbra and penumbra with extreme foreshortening. There is no designation yet that I’ve found for that region.

A wide patch of facula was on the western limb as well, more abundant on the 13th. I believe my placement was off for this patch of facula on one or both of the sketches.


~ by Erika Rix on May 13, 2012.

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