Thoughts from Starlight Cascade

This is the best image of the run of imaging of Jupiter Tuesday evening. The highlight of the night was a double moon shadow transit, Europa first and smallest and second Ganymede and larger.

Form left to right is:

Ganymede shadow, Europa shadow, Europa, Ganymede

seeing was poor, transparency was poor and winds were gusty. Clouds rolled in before the transits were complete 🙁

This is the best image of the 49 runs, the best 10% 10K frames at 3ms ramping up to 10ms at the end of the 49 runs.

Jupiter diameter is only 38 arcseconds
Below is the animated GIF of the 49 runs.

Jupiter Impact Detection

Besides imaging Jupiter for the outofthisworldlisness of Jupiter, its moons transitting the surface, its moon shadows transitting its surface, the Great Red Spot, bands and belts, and many other spots, amateurs can also watch for impacts on Jupiter itself. Anyone remember Comet Shoemaker Levy 9 in 1994?

So.. I have been aware of this concept, and even used the DeTect software package from time to time… but never in a consistent manner. During a Citizen Science Education and Public Outreach Webinar on Feb 23rd, I learned something tremendous. One can install Detect (https://github.com/DeTeCt-PSWS/DeTeCt-MFC/releases/tag/v3.9.0) on the same system as Autostakkert! v4 (https://www.autostakkert.com/) and… wait for it…

autostakkert!v4 will automatically invoke DeTect and have it search for Jupiter Impacts *whilst* at the same time, doing its normal stacking process!

As seen in this image (autostakkertdetect.jpg) .. there is a tiny icon that looks like Jupiter (highlighted) and the check box is now checked after install of DeTect on the system.

I am looking forward to have this additional value added science tool for use in the future. In the meantime you can also run it on the raw saved .SER files from the past. For those RASC-KC members that ask.. why do you save your raw data? This is another great reason!

So I fired up DeTect and aimed it at my online archive of 2025 Jupiter .SER raw video files. Processing those 87 files of approx 528GB will probably take a few hours. Especially since I just saw that there were also some Mars files in there… I wonder what it will do with them? After that I will starting running through 2024, month by month, probably in overnight runs.

This is the realtime display (image detect.jpg) of the software at work.

There is another big impact imaging project aimed at detecting lunar impacts… But I haven’t tried that out yet 🙂

(https://www.nasa.gov/meteoroid-environment-office/lunar-impact-monitoring/)

This evening we went out at -5C thinking it would stay that way and just more than 30 minutes later, we came inside to discover the temp was in fact -16C. The indoor hot chocolate I had formed icecubes when I picked it up!
This was one of only two runs of Jupiter last night. There was a shadow transit!
The moon appearing in the upper right is Io
The shadow is from Europa, which is just out of frame to the right.
Seeing was poor, transparency was poor
Focus… my remote focuser dropped connection.. over and over again. So the focus for this was not spot on at all.
Altitude was good.. almost 58 degrees up. This is the best 15% of 18k frames.
I’ve also started to change my firecapture cutout box from 800×800 to 600×600. As a direct result of that, the frame rate went up even more! I still use an ROI of 1200×1200. Tracking went well.. I did not have to guide at all in two 120second runs.

This was the single best imaging run of 36 runs on a cold evening.
The shadow transit is from Io, the top right moon is Ganymede. Io itself is on the surface of the planet, not easily visible.
Seeing was poor, transparency was poor, and a more than quarter moon was nearby.
Exposures were about 2ms and this was the best 15% of 15k frames. The workflow was: firecapture, autostakkert!, registax, imagemagick, gimp. Not included here is the further processing using winjupos. That will come along shortly.

Below is an animation of the 36 runs of 180 seconds each, totalling 108 minutes

and after even yet more time processing… this is the result of running 36 imaging runs through winjupos to derotate. It was also put back through gimp for black levels, colour saturation and unsharp process (right image).. the left image is the closest timestamped image before winjupos processing.

These results are inconclusive regarding better signal to noise and a better image.

We have a new-to-us Celestron C9.25 Schmidt-Cassegrain OTA and as everyone knows, the front corrector plates on SCT’s are extremely prone to dew. So we have had an external strap heater around the front end (image c925a.jpg).

Unfortunately this strap heater moves around, comes loose, prevents the metal cap from going on, and makes it very difficult to add in the foam dew shield. So we got the Celestron Dew Heater Ring, which mounts on the inside.

Step 1: add a paper safety on the glass (image c925b.jpg)

Step 2: remove the six Phillips head screws

Step 3: remove the existing ring, the gasket underneath

Step 4: install the dew heater ring, adjusted so the power cable is near the 7’oclock position and put the screws back in.

Step 5: run the cables into the cable holder which clips on the edge.

Step 6: Bob’s Your Uncle.

Previous to the work, I watched THREE youtube videos on the process to make me an expert:

and my favourite: https://www.youtube.com/watch?v=2blj_PDthcI

All three video demos went smoothly and the job was done in less than 5 minutes.

I made it to step 2. Step 3, removing the ring and gasket, totally failed. After 20 minutes of trying to pry out the ring without touching the glass (or breaking the glass!!!!) I stopped, reversed and put it all back together again.

I am suspecting that maybe it was that all three demos were done in very warm climates, I was trying this at -4C and that everything (metal bits) had contracted and was jammed together. The alternative is perhaps it was stuck together with adhesive. In any event, I will do some more research and wait for a much warmer day (say +10C or better) and try again.

The last image (image c925c.jpg) is what the dew heater looks like (measured 7 ohms which calculates out to about 20 watts max)