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Chinese Space Station, Globular Clusters

Posted: 28 May 2021

Wednesday, 26 May 2021, was cloudy. There were many lenticular clouds mid-day.


Thursday, 27 May, was clear although it got breezy late in the afternoon.

Open: Thursday, 27 May 2021, 1831 MST
Temperature: 86°F
Session: 1640
Conditions: Clear, breezy

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 14mm 100° eyepiece
2" UHC filter


SYNCed observatory clock to WWV time signals. I then relaxed on the observatory patio bench for awhile and watched the local birds.

1926 MST: sunset.

Prepared the D850 DSLR for prime focus imaging.

1930 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed Venus, 102X. It showed a nearly full disk. Then viewed Mercury, 102X. It showed a nice thin crescent.

Next, I added the TLE parameters for the new Chinese space station Tianhe-1 to the AutoStar.

1944 MST: the breezes had calmed down.

Mounted the D850 DSLR at prime focus, focused on Regulus, and locked the 12" primary mirror. All was now ready for the pass of the Tianhe-1 space station. I then relaxed on the bench again for a few minutes.

1957 MST: back at the 12" telescope I began waiting for the space station to rise.

2000 MST: saw the first Kissing Bug of the season. They will be around until late June most likely.

When Tianhe-1 appeared it was a couple of minutes later than predicted. So I had to play catchup to get it in the telescope. I missed the closest approach and was only able to get some video frames (1080p, 60fps, 1/1250sec, ISO 1600) with it after mid-pass. Here are two images of Tianhe-1 showing a hint of structure. Currently, Tianhe-1 is much smaller than the International Space Station (ISS) but more modules are expected to be added to it.


2013 MST: Kissing Bug #1 terminated.

2020 MST: removed the camera and observed Omega Centauri (globular cluster), 102X, very low in the southern sky. I then relaxed on the bench again while waiting for the sky to get darker.

2030 MST: back in the observatory. Mounted the D850 DSLR at prime focus + UHC filter, focused on Arcturus, and locked the mirror. SYNCed the AutoStar on Arcturus.

2038 MST: Kissing Bug #2 terminated.

2039 MST: StarLock ON.

Imaged these globular clusters, StarLock autoguided, all at the same scale.

Omega Centauri (UHC, 2 minutes, ISO 4000)

M13, Great Globular Cluster in Hercules (UHC, 2 minutes, ISO 4000)

M92, Globular Cluster in Hercules (UHC, 30 seconds, ISO 4000)

2115 MST: StarLock OFF.

The southeastern sky was brightening from the rising waning gibbous Moon.

Removed the camera and UHC filter and viewed the following, 174X: M92 (globular cluster), M13 (globular cluster), M57 (Ring Nebula), M56 (globular cluster), M83 (Southern Pinwheel Galaxy), Centaurus A (galaxy), and Omega Centauri (globular cluster).

2138 MST: LX600 OFF.

Close: Thursday, 27 May 2021, 2146 MST
Temperature: 68°F
Session Length: 3h 15m
Conditions: Clear

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