July 9, 2013: Solar lunch with big arc on western limb

[michael.h.f.wilkinson]

Just been out with the LS35. Skies were partly cloudy, but I was persistent, and when the first gap showed I was rewarded with my first glimpse of a massive arc on the western limb. It is on the southern hemisphere, and appears to touch the limb only on its southern end at the moment. As lunch progressed, the skies cleared a bit more, so I could observe it at my leisure. The surface also showed a lot of detail. AR 1785 and 1787 are still going strong. The complex shows up as a large dark spot trailing a complex pattern of bright structures reminiscent of vortex shedding in turbulent flows. The two dark filaments on the northern hemisphere are still going strong, and a couple of smaller ones have joined them. One or two smaller proms can be seen around the disk, but they are all completely outclassed by the big arc on the west.

[Steve Ward]

Lovely report , much nicer to read this than squinting at the GONG films ...