Cassiopeia Observatory logo

Sunset, Jupiter, Saturn, ISS,
Barnard's Star proper motion

Posted: 19 September 2019

Open: Wednesday, 18 September 2019, 1809 MST
Temperature: 96°F
Session: 1382
Conditions: Mostly clear

Equipment Used:
12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 4X Powermate
Atmospheric Dispersion Corrector


After opening the observatory I went to the house patio to try to observe the planets Mercury and Venus very low in the western sky at sunset. I used 12x50 binoculars for the attempt.

1828 MST: sunset.

Took this D850 DSLR photo (focal length 300mm) just as the sun set behind Picacho Peak.


I continued trying to locate Mercury and Venus, both of which would be just to the left of Picacho Peak, but the haze kept them hidden.


1850 MST: returned to the observatory.

1854 MST: LX600 ON, StarLock OFF, High Precision OFF.

I updated the TLE for this night's good pass of the International Space Station (ISS).

1858 MST: viewed Saturn and three moons, 102X. Then viewed Jupiter and four moons, 102X.

Mounted the D850 DSLR at prime focus + 4X Powermate + Atmospheric Dispersion Corrector. This image of Jupiter is a stack of 1348 video frames (1080p, 24fps, 5X slo-mo, 1/125sec, ISO 3200):


This image of Saturn is a stack of 1072 video frames (1080p, 24fps, 5X slo-mo, 1/125sec, ISO 12800):


1920 MST: ended planet imaging and began preparing for the ISS pass. Mounted the D850 DSLR at prime focus. As an experiment I set the video recording mode to 720p, 60fps, 1/2000sec, ISO 3200. I focused on Saturn and locked the 12" telescope primary mirror. I then began waiting for the pass to start (2003 MST).

1940 MST: breezes began. More clouds were visible.

When the ISS pass began the initial pointing by the AutoStar was off. Once I get the ISS centered in a finderscope tracking was pretty good until the ISS approached the North Celestial Pole (where satellite tracking always gets crazy). Unfortunately, my experiment failed. Using 720p resulted in a too small image scale. And the ISS was overexposed. This frame from the video near mid-pass was upscaled 4X. At least it shows the solar panels.


2021 MST: clouds were increasing. No more imaging this night.

2030 MST: final look at Saturn, 102X.

2031 MST: LX600 OFF.

Close: Wednesday, 18 September 2019, 2042 MST
Temperature: 78°F
Session Length: 2h 33m
Conditions: Partly cloudy, breezy

During the previous session I imaged Barnard's Star. In the report I mentioned that I was not able to scale and rotate the images from 10 June 2013 and 17 September 2019 to match due to using two different telescopes and two different cameras. Later it occurred to me that the MacOS app Observatory might be able to automatically do the scaling and rotating to align the two images. It did the job nicely. Barnard's Star is the moving object just above center:


Comments are welcome using Email. Twitter users can use the button below to tweet this report to their followers. Thanks.

Previous report

Cassiopeia Observatory Home Page

Back to Top

Copyright ©2019 Michael L. Weasner /