Active Solar Limb

Prominences All Around

After two months of cloudy, hot, humid weather a mild, cloud free morning good for solar observing arrived on September 15th. The sky was milky white from high thin haze. Temperature ranged from 72 to 75 degrees during my brief 50-minute observing window. Despite a promising 9:40 am start, clouds began appearing at 10:40 am and atmospheric turbulence increased. I always have to hurry to capture images before conditions worsen.

On this day only a few relatively small sunspots were present, but a nice array of prominences were scattered around the Sun's limb. These prominences were spectacularly bright and clear when viewed through the eyepiece of my solar telescope! Image quality below really doesn't match the eyepiece view this time! I wished I could have shared the view with others, but no one was available or interested, so I enjoyed them alone.

The next image is a 6-panel mosaic of the southern solar hemisphere processed to show prominences around the edge. Although the disc is, consequently, overexposed, you can still see two sunspots. The large arching prominence on the lower left is really grand! Northern hemisphere prominences were also numerous as shown in the next 6-panel mosaic. Activity associated with departing sunspot 3098 in the upper right included some spiky eruptions. These show more clearly if you enlarge the image by clicking on it. Here's an enlargement of sunspot 3098 and its spiky emissions. Two sunspots in the southern hemisphere appear in more detail in the following imperfect 6-panel mosaic processed to show disc detail instead of prominences. Sunspot 3102 is on the left and sunspot 3100 is right of center. Next is a closer view of sunspot 3102. This long lasting sunspot previously disappeared around the Sun's western limb almost three weeks ago. As the Sun rotated it then traversed across the solar back side for almost two weeks before emerging around the eastern limb to appear as it does in the image below. The large arching prominence was near sunspot 3102. The suspended arch was considerably dimmer than its base near the limb. I always have trouble making prominences stand out from noisy background. Prominence detail is hardly improved in the following yellow colored image with blacked out disc. I  look forward to cooler weather and clearer sky as autumn begins.