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In the early morning of December 12th, just after midnight, asteroid 22 Kalliope was in the southeast sky, well positioned for imaging from my backyard. 22 Kalliope was inside the light dome of east Oklahoma City, but the seeing (i.e., the steadiness of the atmosphere) was good. Some of the images I captured of this minor planet follow. All were captured using a Meade SN-8 (203mm f/4) telescope and ZWO ASI224MC camera with UV/IR cut filter.

Wide View

Asteroid 22 Kalliope on 12 December 2021, at 06:01:39 and 06:26:49 UT. Field of view: 20×15 arcminutes. North is up. East is left. [1]
During this session, 22 Kalliope was traveling through the constellation Gemini, showing up well against this field of mostly fainter background stars.  I measured its magnitude at 10.5.  The Minor Planet Center predicted magnitude 10.4, and NASA’s JPL Horizons System predicted magnitude 10.37.

Wide View Animation

Asteroid 22 Kalliope moves through the field of view against a background of far distant stars over a 25 minute period. Field of view: 20×15 arcminutes. North is up. East is left [2]
This wide view animation gives a sense of 22 Kalliope’s motion across the sky. The animation is a 6-image time lapse sequence covering 25 minutes. On this night, 22 Kalliope was moving across the sky at the rate of 0.54 arcseconds per minute. 

Zoomed In Animation

This is a cropped and enlarged portion of the wide view animation above. It gives a closer look at 22 Kalliope. North is up. East is left.

Asteroid 22 Kalliope is main belt asteroid with a diameter estimated as 168 km (104 miles). As a main belt asteroid, 22 Kalliope orbits the Sun between the orbits of Mars and Jupiter. Its orbital period is 4.96 years. At the time these images were captured, 22 Kalliope was 1.728 AU (258,505,100 km/160,627,600 miles) from Earth.

22 Kalliope doesn’t move through space alone. It is accompanied by a satellite asteroid named Linus. Linus is a good-sized asteroid in its own right with a diameter of 28 km (17 miles).  Linus orbits 22 Kalliope at a distance of  1100 km (684 miles) with an orbital period of 3.6 days.[3] 

Notes:

1. December 12, 2021, 06:01:39 and 06:26:49 UT. Stack of two images, each a stack of 10 frames at 30 seconds each (total 300s). Telescope: Meade SN-8 (203mm f/4). Camera: ZWO ASI224MC with UV/IR cut filter. Mount: Celestron CGEM.

2. December 12, 2021,06:01:39-06:26:49 UT. 25-minute, 6-image, animation sequence. Each image a stack of 10 frames at 30 seconds each (total 300 seconds). Telescope: Meade SN-8 (203mm f/4). Camera: ZWO ASI224MC with UV/IR cut filter. Mount: Celestron CGEM.

3.  See, JPL Small-Body Database: 22 Kalliope, https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=22

 

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.