Monday, November 21, 2005

20051120 - Sunday's Sun

Session name: 20051120.1000

This session turned out to be day 4 with Sun. As I told a few of the folks that stopped by, I have been observing changes on Sun. Our star, the one we can see through the veiwing window and through the scope has indeed showed change over the days. I brought only the Tak102 with me to lighten the load. I didn't expect to stay out long nor did I see any value to bring the TVR.

Lotsa folks came through and I don't know if they were New Yorkers or just travelling through. I kind thought that most were tourists, a hunch. Many had stated that this was the first time seeing Sun. Sunspot group 822 was the easiest for most to see and the cyclone-shaped dark umbra continued to be visible as dot on the disk without any magnification. I was somewhat surprised that many noticed the mirror reversal seen through the refractor. Many picked up on this quickly and commented, sort of confirming that they could see the spot through the viewing window.

I didn't attempt to take any pictures today since 2 days resulted in blurry images. So instead I transcribed my notes and sketches to an Alias Sketchpad drawing, as I did in the previous post. I wish I could upload pages from my log directly to the web like Charlie & davep do; it's that "write once, read many" thing.



I felt that the seeing was steadier today, though 91x with the Nagler 9mm eyepeice still required moments of steadiness. The wait didn't seem as long and this seeing would hold for longer periods of time. The sketch above is based on 63x (Nagler 13mm) and 91x. (Venus looked very crisp today and was able to hold up well for 91x).

Sunspot group 824 appeared on the SE limb. It was really foreshortened, most evident by the shape of the penumbra as it hugged the sides of the umbra. The umbra appeared foreshortened as well, and a second umbra was detected below and just outside the penumbra. Faculae was discernable along the area between the sunspots and the limb. For me, the upper part was a loose, script y-shaped and below it was an arc which appeared granualted or spotted, in other words, the faculae was not an evenly bright line, but spotted marks of brightness. Could have been an effect of seeing, though I saw it on more than one occasion.

Sunspot group 822 seems to be losing the faint smaller spots. Is the large umbra/penumbra eating them up or are they short lived? Dunno, some more learning, food for thought. The large umbra is a cool looking cyclone shape, the curving tail twisting up. When seeing was grand, the edge of the umbra appeared uneven, jagged, as it intruded in the penumbra.

Lastly, Sunspot group 823, two days old, now appeared as three spots. The inner one appeared as two the previous session and seems to have merged. The elongated spot could be suffering foreshortening or the joining of the two.

Spaceweather.com's picture for Sunday's sun.

I'm back to work and the weather is overcast - good timing. While Moon has been up in so-so evenings, intruding on some of the deepsky stuff, Sun was fun to watch. I do want to get back to the dark skies in the north of the park . And I hope that some of the folks I met during these day runs will come by to see the sky at night up at Top of the Lawn.

peter