Thursday, December 9, 2021

Comet 2021 A1 (Leonard) - December 2021


Comet C/2021 A1 (Leonard) has been a challenge to view because the weather here in Northern Utah has been quite cold recently. Several mornings the temperature here was 19 degrees F. In spite of the cold on the morning of December 4, 2021 I arose at 4:50 am, dressed warmly and walked out to my observatory. I noticed the sky was dark and clear. Moving the roof off my observatory I started my telescope, camera, and computer and pointed my telescope to the eastern part of the sky near the constellation Boötes using the planetarium program Cartes du Ceil. Luckily when I took my first picture the comet appeared off center to the right side of the picture just above center, which was just where I wanted it located on the frame. Then setting up a camera sequence using Nikon Back Yard software I began to expose the images I took that morning.

Below is a movie I made from taking about 50 images over the course of about an hour and a half, until the sky became too bright because of morning twilight. My instrument that morning was a 12 inch LX200 R telescope, with a NIKON D5100 DSLR camera attached. Each image taken was 30 seconds long with a one minute pause between exposures. The resulting movie was pleasing to me as it showed the movement of the comet as it glided across a short arc of the sky. The movie was made using the Windows 10 Photos App.


Finding the comet in my binoculars was also a challenge during the first part of December, it barely being visible in my 10 x 42 mm Vixen Diamondback binoculars. The first time I saw the comet, it was a faint smudge, but the comet core increased in brightness over the next several days and soon became easy to spot, but the tail continued to be quite dim. Unfortunately it will probably not be visible in this location at its brightest on December 12 as it may be cloudy that morning because of the snow storm we are experiencing tonight and the next few days. But I hope to see the comet in the western sky soon as it swings around to that part of the sky.