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Asteroid 3 Juno & Messier 10 Globular Cluster

Posted: 19 June 2021

Friday, 18 June 2021, dawned clear with some smoke in the sky. The Telegraph Fire 70 miles north of Oracle was now at 173,202 acres burned with 70% containment. The Mescal Fire, also 70 miles north of Oracle, was 72,250 acres burned with 100% containement.

Open: Friday, 18 June 2021, 1829 MST
Temperature: 99°F
Session: 1648
Conditions: Mostly clear, smoky

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

iPhone 11 Pro

Opened the dome and then relaxed on the observatory patio bench.

Using the D850 DSLR camera with a 150-600mm lens I took the following photos of wildlife (focal length 600mm, cropped).

House Finch

Collared Lizard

Gila Woodpecker

Redtailed Hawk

1927 MST: took this iPhone 11 Pro Max wide-angle lens photo of the sky showing the setting Sun and the smoky sky.


1934 MST: the Setting Sun (and sunspot AR2833), D850 DSLR (f/11, 1/400sec, ISO 500, FL 600mm).


1937 MST: sunset.

Prepared the D850 DSLR for prime focus imaging.

1943 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed Venus, 102X. Then viewed the Moon, 102X.

Mounted the D850 DSLR at prime focus + focal reducer. Took this photo of the Moon (1/250sec, ISO 200).


Did some lunar observing, 102X.

1958 MST: dome OFF.

Returned to the bench.

2030 MST: viewed M53 (globular cluster), 102X.

Mounted the D850 at prime focus + focal reducer. Tried to image the globular clusters NGC5053 and M53 in the same field-of-view. Unfortunately, the separation was just slightly too much for my equipment.

Removed the focal reducer, focused on Vega, locked the 12" primary mirror, and slewed to M10 (globular cluster). Did some framing test images.

2119 MST: StarLock ON.

2120-2220 MST: took three images of M10 and Asteroid 3 Juno, StarLock autoguiding, 15 seconds, ISO 6400, 30-minute intervals. Breezes had come up by the time I began imaging, which impacted autoguiding. The best image was at 2220 MST.


This animation of the three images shows Asteroid Juno moving over the one hour.


2221 MST: StarLock OFF.

2228 MST: viewed M10 and Asteroid 3 Juno, 102X.

2229 MST: LX600 OFF.

2232 MST: dome ON.

Close: Friday, 18 June 2021, 2242 MST
Temperature: 85°F
Session Length: 4h 13m
Conditions: Mostly clear, smoky, breezy

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