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Comet C/2021 A1 (Leonard)

Posted: 15 December 2021

Sunday, 12 December 2021, dawned clear, but some clouds began arriving mid-day. I tried to observe Comet C/2021 A1 (Leonard) very low in the western sky after sunset. However, the twilight sky, the comet's faintness, and some clouds along the western horizon prevented seeing it. Monday, 13 December, was cloudy. With rain in the forecast again, I put the Dome Cover ON. Rain arrived Tuesday morning, 14 December, with a total of 0.17".

There was 0.32" rain Wednesday morning, 15 December. The sky mostly cleared after sunset, giving me a chance to try for Comet C/2021 A1 (Leonard).

7x50 binoculars


1810 MST: After a couple of minutes of searching, I observed Comet C/2021 A1 (Leonard) in the twilight sky using 7x50 binoculars. It was low in the southwestern sky, to the lower right of the planet Venus. No tail was visible in the binoculars. The comet was not visible to the naked eye.

I began taking some photos using a D850 DSLR with a 70-300mm lens. Here are some of the photos (f/5.6, 1 second exposures). The first photo shows Venus at the upper left and Comet Leonard just below center. The second photo shows Venus at the upper left and the comet just above the tree below center. My moonlit observatory dome is behind the tree in the lower lefthand corner. For the third photo I changed my location slightly. The comet is at the center.

ISO 1600, FL 80mm
Click or tap on image for larger version

ISO 1600, FL 80mm

ISO 6400, FL 300mm

1842 MST: the comet was no longer visible in the binoculars seven minutes before it set. There were some clouds and haze along the horizon that interfered.

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