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Mercury, Zodiacal Light, Markarian's Chain

Posted: 8 May 2021

Clouds and wind arrived mid-day on Thursday, 6 May 2021. The sky was clear on Friday, 7 May, but there was still some wind. I decided to open the observatory with the hope that the wind would decrease after sunset (which some forecasts said it would do; other forecasts said it would continue into the night).

Open: Friday, 7 May 2021, 1832 MST
Temperature: 85°F
Session: 1633
Conditions: Clear, windy

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
1.25" 15mm eyepiece
Atmospheric Dispersion Corrector
2" 2X Powermate

iPhone 11 Pro Max

After opening the observatory I relaxed on the observatory patio bench.

1913 MST: sunset. Calmer now.

1914 MST: LX600 ON, StarLock OFF, High Precision OFF.

1916 MST: viewed the planet Mercury, 102X. Half phase visible. Then viewed Mercury, 325X + Atmospheric Dispersion Corrector. Nice view.

Mounted the iPhone 11 Pro Max on the 15mm eyepiece and took a 30 second video using NightCap Camera (ISO250, 1/1000sec, 1X lens). This is a stack of the 912 video frames, afocal 325X.


Viewed Venus, low and through tree branches, 325X + ADC. Too low for a good view. Viewed Venus, 102X. Better view of the nearly full disk.

1940 MST: dome OFF. Calm now.

Relaxed on the bench to watch the stars come out.

2003 MST: took this handheld D850 DSLR photo (f/2.8, 1/4sec, ISO 12800, White Balance 5560K, 14mm UWA lens) of the western sky. Can you spot the planet Mercury low in the sky and the planet Mars higher up? Mouseover or tap on the image for labels.

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2014 MST: the Zodiacal Light was becoming visible in the western sky.

2031 MST: took this handheld D850 DSLR photo (f/2.8, 1 second, ISO 12800, WB5560K, 14mm UWA lens) of the Zodiacal Light in the western sky. Mouseover or tap on the image for label.

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2038 MST: back inside the observatory.

Mounted the D850 DSLR at prime focus + focal reducer + UHC filter to image Markarian's Chain of galaxies.

2045 MST: StarLock ON.

Took several images but StarLock autoguiding was very erratic this night. Maybe poor seeing? I gave up on trying long exposures with the UHC filter. Removed the filter, but could only manage one good exposure (1 minute, ISO 12800, WB5560K).

Mouseover or tap on image
Mouseover or tap on image for labels

2140 MST: StarLock OFF.

I will try again on another session. Unfortunately, I am not able to get the entire Chain of galaxies in the field-of-view with the 12" telescope.

2147 MST: LX600 OFF.

2154 MST: took a Sky Quality reading and reported the result to Globe at Night.

2200 MST: dome ON.

Close: Friday, 7 May 2021, 2205 MST
Temperature: 66°F
Session Length: 3h 33m
Conditions: Clear, SQM 21.24

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