Giant Prominence

Solar Limb Action

Solar activity is increasing slightly quicker than expected. On October 2nd observing conditions were too good to pass up. Not even one cloud appeared in the blue sky, and the temperature hovered near 70 degrees. During the first look through the eyepiece of my solar telescope I was surprised to see one of the largest, brightest prominences I've ever observed! It arched high above the limb as you can see in the first image below.

One sunspot group was visible on the disc, but prominence action around the limb was more interesting on this day. The next picture is a 5-panel mosaic showing the western limb. (Click on the images to see more detail in expanded views.) 

Another nice prominence on the southeastern limb is shown in the following 6-panel mosaic.

The prominence in the southeast was near a small filament shown in the next image. 

A nice sunspot group called 2880 was nearly centered in the Sun's northern hemisphere. Click on the next image to enlarge it. Notice the s-shaped light bridge dividing the umbra on the right.

The light bridge is a region of lower magnetic field compared to magnetic field in the darker neighboring umbra. The weaker field allows more convection of hotter material from below, so the light bridge appears brighter than the cooler, darker umbra. The appearance of light bridges in an umbra usually signals the decay of a sunspot. Next is another view of sunspot 2880 in red light not specifically from excited hydrogen gas. The light bridge seems even more striking here. 

Sunspot 2877 was about to rotate out of view near the western edge of the Sun's disc. Although almost unnoticeable in the first 5-panel mosaic image above, it shows up clearly in the next red light image.

I'm still looking for a way to get better flat field images to eliminate brightness variations across my images.