Sunspot Departs

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On April 16th I observed the Sun with my young friend, Luisa, a bright, curious international student from Brazil. Luisa has a deep interest in physics and astronomy. I feel so fortunate to be able to share common interests with Luisa. April 16th was a nearly perfect day with few clouds, light wind, low humidity, and temperatures in the mid to upper 60's.

We began using my troublesome new ZWO ASI 1600MM camera. From the start flashing horizontal lines were present on the laptop preview screen. I had hoped they would disappear when using a powered USB hub, but the powered hub by itself made no difference.

With Luisa's help, we were able to prove there is a faulty USB connection between the camera and laptop. She gently moved the USB plug at the camera while I looked at the preview screen. Sure enough, horizontal lines increased or decreased depending on how the plug was moved. There is a faulty connection right at the camera's USB plug on the camera body. The plug itself seems to be loose.

With Luisa holding the plug so that no lines were visible I captured the first image below showing sunspot 2738 approaching the Sun's western limb.

The picture above shows the kind of image the 1600 camera could produce if it were functioning properly.

With Luisa continuing to hold the USB plug, I took another image of the sunspot using a smaller region of interest.

Six days ago the umbra was split into two dark parts separated by a brighter dividing line. On this day the lower umbra was lighter than the upper portion.

Since the 1600 camera was malfunctioning, I decided to pack it up and use my trusty old ZWO ASI 174 camera instead. It has a smaller field of view, but at least it works as it should. The sunspot looked just as good with the older camera, but the reduced field of view is apparent if you compare the next image with the first image above.

As clouds increased I took three more images to blend together into the following three-panel mosaic.

Images from the old camera blended beautifully into a mosaic. In previous attempts, however, images from the new camera seemed to challenge and defeat all my mosaic building software.

I'm in the process of trying to return the 1600 camera, but don't know if this will be possible.