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International Space Station crossing the Moon

Posted: 13 November 2019

I delayed going out to the observatory due to strong winds that were blowing at sunset. As the atmosphere was "disturbed" I decided to defer doing my first Deep Sky Object image capture using my new Optolong filters until another session. But I did want to try to capture the International Space Station (ISS) crossing the Moon this night. This is the prediction by


Open: Tuesday, 12 November 2019, 2011 MST
Temperature: 60°F
Session: 1406
Conditions: Clear, windy

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


I delayed opening the dome due to the wind. I SYNCed the observatory clock to WWV for the upcoming ISS pass. I then prepared the D850 DSLR for prime focus imaging.

2029 MST: dome open.

2030 MST: LX600 ON, StarLock OFF, High Precision OFF.

2032 MST: viewed the just past Full Moon, 102X. A slight terminator was visible.

Mounted the D850 DSLR at prime focus. Took this photo of the Moon (1/400sec, ISO 100).


Next, I did a test video recording of the Moon in preparation for the ISS crossing of the Moon.

2048 MST: all was ready for the ISS-Moon transit. Closed the dome due to the wind.

2115 MST: dome open. Still windy. Seeing was definitely "disturbed" by the wind.

2124 MST: I began doing a video recording of the Moon (1080p, 60fps, 1/3200sec, ISO 1250). 212557 MST: I saw the ISS zoom across the Moon on the DSLR Live View screeen. That was neat.

This is the video (less than 1 second) showing the ISS and the effects of the strong wind on the telescope.


This is a merge of six video frames showing the ISS crossing the Moon.


I wish it hadn't been so windy. Poor seeing and the telescope movement really affected the clarity of the ISS. But the structure is still obvious.

2130 MST: last look at the Moon, 102X.

2131 MST: LX600 OFF.

Close: Tuesday, 12 November 2019, 2140 MST
Temperature: 55°F
Session Length: 1h 29m
Conditions: Clear, windy

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