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Mercury, Virgo Galaxy Cluster observing,
SpaceX Starlink Satellites

Posted: 6 May 2021

Open: Wednesday, 5 May 2021, 1836 MST
Temperature: 86°F
Session: 1632
Conditions: Mostly clear

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

iPhone 11 Pro Max

1844 MST: LX600 ON, StarLock OFF, High Precision OFF.

Slewed to the planet Mercury. It was not yet visible.

Relaxed on the observatory patio bench.

1900 MST: Mercury was now visible, 102X. A near half-phase was visible. Switched to the 15mm eyepiece (163X) and Atmospheric Dispersion Corrector. The view of the planet, low in the western sky, was improved.

Mounted the iPhone 11 Pro Max on the 15mm eyepiece using the Levenhuk adapter. Did some video recordings of Mercury. This is a stack of 916 video frames taken using the iOS app NightCap Camera (ISO 21, 1/978sec, 30 seconds, 2X lens), afocal 163X + ADC.


1911 MST: sunset.

1920 MST: viewed the planet Venus, 163X + ADC. The planet was viewed through tree branches. A nearly full disk was visible. Viewed Venus, 102X.

1925 MST: relaxed some more on the bench while watching the stars come out. Studied some charts of the Virgo Galaxy Cluster, which would be my main observing target for the night.

1948 MST: dome OFF.

2030 MST: back inside the observatory.

Began observing galaxies in the Virgo Galaxy Cluster. Over the next nearly one hour I observed the following galaxies, 102X: M84, NGC4388, NGC4387, M86, NGC4402, NGC4435, NGC4438, NGC4458, NGC4461, NGC4473, NGC4479, NGC4477, NGC4459, and NGC4474. These galaxies are part of "Markarian's Chain" in the Virgo Cluster. Then observed M87, M88, M89, M90, NGC4571, M91, M85, NGC4394, NGC4440, and NGC4450.

2058-2001 MST: As I was documenting my galaxy observations in my logbook a bright string of lights in the constellation of Auriga caught my eye. It was a train of SpaceX Starlink satellites that had been launched from Florida the day before. I wished I had not put my 70-300mm telephoto lens on the D850 DSLR camera (to photograph any wildlife I saw from the observatory before sunset). But that's what I had so I began taking handheld photos of the Starlink satellites. These photos were taken at f/4.5, ISO 12800, focal length 70mm using various shutter speeds. The fixed bright star near the center of the photos is Capella in the constellation of Auriga. As can be seen from the photos, the satellites were very bright. Although not seen in the photos, some of the satellites flared and were briefly brighter than Capella. The slower shutter speeds show the movement of the satellites.

Shutter speed: 1/15sec

Shutter speed: 1/5sec

Shutter speed: 1/4sec

Shutter speed: 1/4sec

Shutter speed: 1/2sec

I did not count the satellites but there were probably at least 50 seen in the 3 minutes that they were visible moving low across the northern sky from the northwest to northeast.

After the Starlink pass was over I resumed observing galaxies in the Virgo Cluster, 102X: M100, NGC4298, NGC4302, M99, NGC4216, NGC4429, M49, NGC4470, NGC4564, NGC4567, NGC4568, and M58.

In total, I observed 36 galaxies in the Virgo Cluster.

2125 MST: observed Omega Centauri (globular cluster) low in the southeast sky, 12x50 binoculars.

Then viewed M83 (Southern Pinwheel Galaxy), 102X.

2128 MST: LX600 OFF.

2133 MST: dome ON.

2142 MST: took a Sky Quality reading and reported the result to Globe at Night.

Close: Wednesday, 5 May 2021, 2148 MST
Temperature: 68°F
Session Length: 3h 12m
Conditions: Clear, SQM 21.19

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