I went back for another shot at Comet C/2021 A1 (Leonard) in the early morning hours of November 29th. At around 04:30 a.m. the comet finally climbed above the trees and roofline and I was able to get to work.
The imaging conditions weren’t ideal. There was a bright waning crescent Moon nearby and I was looking to the southeast into the eastern side of the Oklahoma City light dome. Nevertheless, I did capture some images. Here’s what I caught.
This single image is actually a stack of 36 separate images. Each image in the stack was aligned on the comet, essentially holding it stationary against the east-to-west movement of the night sky. The stars, on the other hand, continued to move, leaving trailed images. The star trails indicate the direction of the comet’s movement. The comet’s tail points away from the Sun.[1]This time-lapse animation covers nearly an hour’s worth of movement. At the time these images were captured, Comet C/2021 A1 (Leonard) was moving at approximately 3.5 arcminutes per hour across a rather barren patch of sky in the constellation Coma Berenices. The field of view of this image is approximately 18×14 arcminutes. North is up. East is left.[2]At the time these images were captured, observers were reporting A1 Leonard’s brightness as being between magnitudes 7-8. But, the comet is expected to brighten considerably during this next week. It should be a good binocular object at magnitude 4-5 December 6-10. It will rise around 03:00 a.m., and between 05:00-06:00 a.m. will still be low in the east, but high enough to be seen. After December 10th, Comet A1 Leonard drops lower and lower in the eastern sky and will be lost in the sunrise.
Notes:
1. Comet C/2021 A1 (Leonard), November 29, 2021, 10:54:49-11:59:28 UT
Stack of 36 images. 6 frames per image at 20 seconds per image (120 seconds total integration).
Telescope: Meade SN-8 (203mm f/4). Camera: ZWO ASI224MC.
2. Comet C/2021 A1 (Leonard), November 29, 2021, 10:54:49-11:59:28 UT.
31-Image time lapse animation sequence. 6 frames per image at 20 seconds per image (120 seconds total integration). Telescope: Meade SN-8 (203mm f/4). Camera: ZWO ASI224MC.
