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Special Visitor, Comet C/2021 A1 (Leonard),
Full Moon on Dome

Posted: 19 December 2021

Friday, 17 December 2021, was cloudy. The sky cleared on Saturday, 18 December. I removed the Dome Cover in anticipation of opening the observatory that evening.

Open: Saturday, 18 December 2021, 1701 MST
Temperature: 63°F
Session: 1705
Conditions: Clear

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 30mm eyepiece

iPhone 13 Pro Max

SYNCed observatory clock to WWV time signals.

1710 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed the planet Venus, 102X. A nice crescent phase was visible.

Took this handheld iPhone 13 Pro Max afocal 102X photo of Venus using NightCap Camera (ISO 34, 1/8000sec, 1X lens).


1720 MST: Sunset.

I then relaxed on the bench at times while waiting for the sky to get darker.

1740 MST: Viewed Venus, Saturn, and Jupiter, 12x50 binoculars.

1742 MST: Chad Tolly arrived at the observatory.

1750 MST: Wi-Fi ON.

Used SkySafari 7 Pro on the iPhone to GOTO Comet C/2021 A1 (Leonard). The comet was not yet visible in the 12" telescope or in binoculars.

1806 MST: Comet C/2021 A1 (Leonard) was now faintly visible, 12x50 binoculars.

1810 MST: viewed Comet Leonard with the 12" telescope, 81X. It was getting low and into a tree near the observatory.

1815 MST: the comet's tail was faintly visible, 12x50 binoculars.

1825 MST: viewed the comet, 81X and 102X. The tail was faintly visible.

1832 MST: Comet C/2021 A1 (Leonard) was now faintly visible to the naked eye.

1836 MST: final look at the comet through the 12" telescope, 102X. It was finally well into the tree.

1837 MST: Wi-Fi OFF.

I then took the following photographs of Comet C/2021 A1 (Leonard) using the D850 DSLR with 70-300mm lens mounted on a camera tripod. The short faint tail is visible extending about 10 o'clock from the comet's head. The planet Venus is the bright object to the right of the comet.

Click or tap on image for larger version


1846 MST: Viewed the planets Saturn and Jupiter, 102X.

1855 MST: Viewed the bright Moon, about 3 hours before exactly full, 102X.

Took a handheld photograph of the Moon on the observatory dome using the iPhone 13 Pro Max (Night Mode, 3 seconds, 1X lens). That's Chad. He then took a handheld photograph of me in the observatory.


I then took this handheld iPhone 13 Pro Max afocal 81X photo of the Moon using NightCap Camera (ISO 34, 1/2200sec, 1X lens).


1910 MST: Chad left.

1916 MST: LX600 OFF.

Close: Saturday, 18 December 2021, 1923 MST
Temperature: 46°F
Session Length: 2h 22m
Conditions: Clear

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