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Mr. Spock's Home Star,
Two Moons on Dome

Posted: 18 March 2022

Wednesday, 16 March 2022, was clear but very windy with a dusty sky. Thursday daytime, 17 March, was clear and less windy, but clouds began appearing before sunset.

Open: Thursday, 17 March 2022, 1811 MST
Temperature: 80°F
Session: 1736
Conditions: Partly cloudy

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
1.25" 15mm eyepiece
2" 9mm 100° eyepiece
2" 30mm eyepiece
Binoviewers, 26mm eyepieces

iPhone 13 Pro Max

1818 MST: LX600 ON, StarLock OFF, High Precision OFF.

1836 MST: Sunset.

Relaxed on the observatory patio bench for a few minutes while waiting for the sky to get darker.

1850 MST: Back inside the observatory.

1851 MST: Wi-Fi ON.

Used SkySafari 7 Pro on the iPhone to GOTO 40 Eridani (also known as Omicron² Eridani). This is Mr. Spock's (Star Trek) home star with the planet Vulcan.

1858 MST: The nearly full Moon was rising over the hill to the east.

Viewed 40 Eridani, 163X and 271X. The primary star, 40 Eridani A (Mag. +4.43, main sequence star) and the secondary star, 40 Eridani B (Mag. +9.52, white dwarf star) were easily seen. The tertiary star, 40 Eridani C (Mag. + 11.17, red dwarf star) was not yet visible in the bright sky.

1903 MST: Wi-Fi OFF.

1910 MST: 40 Eridani C was now faintly visible, 271X.

Mounted the iPhone 13 Pro Max on the 9mm eyepiece using the Levenhuk adapter.

1915 MST: StarLock ON.

This is 40 Eridani A, B, and C, taken with the iPhone 13 Pro Max and NightCap Camera (Long Exposure, ISO 1600, 1sec, 1 minute exposure, 1X lens), afocal 271X, StarLock autoguided.


1920 MST: StarLock OFF.

Viewed 40 Eridani A, B, and C, 271X, 163X, and 102X. All three stars were easily seen at all magnifications. Thanks to Tim Hunter for the observing tip!

Viewed the nearly full Moon, 102X and 81X. A very slight terminator was visible.

1931 MST: Took this handheld iPhone afocal 81X photo of the Moon using NightCap Camera (ISO 34, 1/16000sec, 1X lens).


I then viewed the Moon, binoviewers, 94X. The entire lunar disk was not visible in the field-of-view.

This D850 DSLR photo (f/11, 30 seconds, ISO 2500, FL 24mm) shows the "Two Moons" projected onto the observatory dome.


1950 MST: Last look at the Moon, 102X.

1951 MST: LX600 OFF.

Close: Thursday, 17 March 2022, 1959 MST
Temperature: 57°F
Session Length: 1h 48m
Conditions: Mostly clear

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