Solar Fireworks

July 4th Sunspot Explosion

Overnight between July 3rd and July 4th hurricane Arthur moved up the east coast and closely approached Williamsburg. The picture below shows the storm on July 3rd just before it moved past Virginia. The red dot on the left above the hurricane is very near my observing site.

The sky unexpectedly cleared after noon on July 4th immediately after hurricane Arthur passed, but it was quite windy. Since the Sun was exhibiting quite a large number of sunspots, I decided to try observing despite the wind. Wind gusts moved the cardboard box used to shade my laptop. The dark cloth draped over my head to prevent light reflections from the computer screen was flapping like crazy. Several twist ties from my electric cables, normally left lying on my observing table, blew away never to be seen again. Surprisingly, in spite of strong winds, the seeing was good, and video images on my laptop screen were very steady.

The first picture below shows the proliferation of sunspots on the Sun's left (eastern) side. It is a 22-image mosaic made with a 2X Barlow lens. Above center, enclosed within a parentheses of dark filaments, is sunspot 2106. Tiny spot 2102 is to the right of 2106. Below center is triple umbra sunspot 2104. The large single spot below and left of 2104 is 2107. Moving left, we come to sunspot pair 2108 and 2110. Large spot 2109 is left of the pair. Finally, small spot 2111 is closest to the Sun's left limb. (Click on the image for a larger view.)

The next image shows a magnified view of sunspot 2106 with small spot 2102 off to the lower right. If you click on the image and reveal more detail, you can see the nonuniform, spotted blackness of the dark umbra on 2106.

The different shades of blackness also appear in the umbras of sunspots 2104 and, especially, 2107 in the lower left of the next picture.

Finally, large sunspot 2109, on the left below, also exhibits a splotchy umbra. Magnetic field arches stretch between spots 2110 and 2108 on the right.

I'm glad I ventured into the wind to observe this fine July 4th display of solar fireworks.