Saturn, Jupiter and Moon

My objective for this session was to image Saturn, Jupiter and the Moon with the ASI290MM. This was a productive and enjoyable session.

It was dark enough that I could have finished polar aligning and started work before 2000. I elected to go with the polar alignment from well over a week ago. I had to manually guide a little more than last time, but not too bad. I checked collimation and found it perfect. Seeing seemed to be about 5-6/10, and probably got worse during the night.

Saturn cleared the trees at about 2100. It took me about 30 seconds to get the planetary targets onto the display after slewing and pointing as best I could using the eyepiece. I found that I had left the Telrad on the last time I used it, but everything else worked perfectly and I fumbled around only a little. It got very dewy as the night wore on, but the heater stayed ahead of it. It got a little cool toward the end, so I put on a light jacket and was comfortable. I hit the western safety limit and I had nearly ran out of storage at around 0110 and came in. All in all I really enjoyed it.

I first shot Saturn in 13 LRGB runs. I manually commanded all filter changes, planning to focus between each filter change. I found that the seeing was not good enough that I could confidently achieve good focus. After reaching green and giving it my best shot, I stopped focusing between filters.

I then went on to shoot Jupiter in 13 IRRGB runs. I focused using G and used autorun to capture these runs. I noted that Io was approaching the limb, but I had time to grab some shots of the Moon before it crossed the limb.

On the Moon, I shot something (cannot remember what) in IR only, then went on to find Mons Rumker, Marius Hills, and the hilly/volcanic area north and west of Aristarchus all near the terminator. I could not resist shooting them in IRRGB – one run for each location. I did 5000 frames of IR and 3000 of each color channel for the color shots.

I then when back to Jupiter and found Io almost at Jupiter’s western limb. I started shooting IRRGB sets in FC Autorun. I wanted to track Io as far across the disk as possible, and its shadow and GRS when they followed. I got about 30 sets before I ran out of laptop storage. I think switched the FC directory to the SD Card and got about 30 more sets before the mount hit the western safety limit. I couldn’t see Io because it was blended into Jupiter’s disk, but I think that it was close to emerging. Its shadow was more than half way across the disk, and the GRS was well in view. I think that I was shooting 2-minute sets for over 90 minutes!

Processing will probably be a challenge, in that I have very little storage for making PIPP runs on the planets. I think that I can “dig” myself out by processing the lunar first (will not process lunar in PIPP), and delete the video files. I can probably transfer some stuff to OneDrive, but that can be slow and painful.

I want to do two experiments with the extended number of sets that I shot of Jupiter/Io. I am interested in seeing how WinJuPos handles a moon transit. I know that the ephemeris will show a moon that is in the field of view, but can it derotate both Jupiter’s disk and a moon that are moving at different rates? The second thing that I want to do is make an animation of Io, its shadow, and the GRS moving across Jupiter’s rotating disk.

Things to do: I want to move the 12v – 3v converter from the old Telrad to the new one. Probably won’t get to that today.

Seeing looks to be better tonight. GRS will be well in view as Jupiter clears the trees. Europa will be arriving at Jupiter’s limb for a transit that begins much later – don’t think that I am going to stay around for that. If the seeing is as good as it is supposed to be, I want to see if I can capture Saturn’s Encke gap. I need to get busy and clear some storage so that I can image again tonight if I am able to get out again.

The Moon - 2021-09-19 02:50 UTC - The Marius Hills
Marius Hills
Moon - 2021-09-19 02:41 UTC - Aristarchus Plateau
Aristarchus Plateau
Moon - 2021-09-19 02:31 UTC - Mons Rumker
Mons Rumker

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