“UFO Galaxy” NGC2683

NGC2683 is a spiral galaxy in the constellation Lynx. It is viewed nearly edge-on from Earth. Because of its appearance, it was nicknamed the "UFO Galaxy" by the Astronaut Memorial Planetarium and Observatory site.

Redshift data indicate that the galaxy is 18 million light-years away from Earth, although its peculiar recessional velocity adds uncertainty to a reliable estimate of its distance. The galaxy has a visible magnitude of 9.8 and an apparent size of 9.3 by 2.2 arc-min.

While historically considered to be an unbarred spiral galaxy, recent data on irregularities in the velocity distribution of stars in the central region suggest it has a barred structure. The galaxy’s inclination from our line of sight makes the presence of a central bar difficult to ascertain visually. There are no recorded deliveries of liquor, pretzels, or bar stools to the core of the galaxy.

I had a unique issue in collecting and processing the data for this image. When I pre-processed the first night of luminance exposures, the resulting stack had numerous subtle artifacts and dust-doughnuts that were not removed by flat-field calibration. The doughnuts were slightly larger than usual and appeared to have moved compared to the flat-field master. I assumed that some dust on the filter moved or that the wheel did not center the filter properly. The next day I redid my flats and recalibrated. The images were slightly different, but not better. So I removed the camera from the scope, carefully capped the nosepiece, and opened up the filter wheel on my kitchen table. I removed and cleaned all the filters and reassembled the wheel. I captured another night of images along with new flats. Everything was still a mess. I removed the camera again but, in my haste and frustration, I failed to cap the nosepiece. When I get the camera inside under the light, there it was … my problem. A tiny spider had made its way into the nosepiece and built a web. Several tiny specks of dust (maybe pollen) settled onto the web and were suspended just above the surface of the filters. As the scope moved across the sky, these specks moved a sufficient distance to mess with my results and my nerves. After cleaning the nosepiece, everything was fine.

I hope you enjoy the image!

Reference sites used for this narrative:

NGC 2683 - Wikipedia

NGC 2683 (seds.org)

New General Catalog Objects: NGC 2650 - 2699 (cseligman.com)

https://www.easternflorida.edu/community-resources/planetarium/