Heads up! Some interesting Jovian moon interactions coming up
Hi all, I've always been interested in the planets and their moons, and I recently came across an interesting fact about 2021 in that the tilt of Jupiter relative to the Earth now allows for occultations of some of the Jovian moons as viewed from Earth. The most spectacular of these will occur on the night of August 15th (Australia time) when Europa will pass behind Ganymede while both are transiting the Jovian disc. I don't know if this has ever been recorded on Earth before, but it's an opportunity not to be missed for imaging.
After looking at this event, I had a look at some others using the Ephemeris tool in WinJupos, and found some other "interesting" moon transits. I have only included the ones for my location in Melbourne Australia, but others in Australia should have a similar view. Hopefully we will be able to capture some of these events, for those of you in other parts of the world I would encourage you to do what I did in WinJupos for your location.
Thanks for posting. It's hard to be on top of everything that's going on. i really appreciate it when people give a heads up on upcoming events, and this is certainly one to watch out for. Of course It will be cloudy in Melbourne then, but it will be nice to know it's going on behind the clouds! :-D :-D
Am aware of the moon events of the 15/16th August thanks to all the info in the Quasar 2021 Astronomy book, which is a wealth of information, ( have no affiliation with the company other than bought every issue since 1998 ).
Just hope that the evening is clear and good seeing for the consecutive transits of the moons. Should be quite a nice show that doesn't occur very often.
Yep I saw it through- just turning in for the night now. Conditions were a bit disappointing compared to the last couple of nights. A few (very few) decent periods and managed to ge the binoviewers on the second scope.
hope to get some images (and maybe even some animations) together.
A complete bust down here in Melbourne. The clouds came through at about 6pm and didn't let up the entire night. I got a few 30 seconds patches through some holes in the dense clouds as Callisto was transiting, but then it completely clouded over and patches of rain started.
Really disappointing, hopefully someone across Australia got something...
Ended up imaging the whole thing until ~4:00am then it was getting low under 30 degrees. It was clear so I can't complain but the sky was turbulent. I used an IR filter so that helped a bit. I can see the shadows very clearly. Seeing the moons against the planet background is going to be hard though. Loads of files to go through. I did sequences of 60s in 90s intervals @97fps so it's about 5000 frames max per segment to play with. Half a TB of data though. Copying now to the main PC. It's taking ages.
Like many others I had been eagerly awaiting last nights events. Had the scopes set up outside before dinner but was not happy with what I could see.
The seeing was absolute garbage, Pickering 2 at best, almost unusable. Anyway, persevered and captured a few videos of Callisto and shadow using the 10"newt at f6. Tried with the Powermate but was a waste of time because of the seeing. Could barely make out the shadow visually through the newt or the 5" apo at 150X.
As the night turned to morning the seeing worsened while waiting for Ganymede and Europa to begin transiting. I did take some more video but had no delusions about what may be extracted from them. All up about 40 Gb when debayered, most of which will need to be deleted , as they portray a mushy mess. At best there may be about 10% of usuable frames so will try.
Overall, a most frustrating and disappointing night , I hope that others around the country had better conditions and enjoyed the show.
My view of Callisto and shadow attached.
Its such a shame that the local conditions appeared to be quite poor for most of those that monitored this event.
I didn't collect much up in Brissie, here is the best I could do.
I've included a screen capture from Autostakkert as it was trying to make some sense of the seeing mess. Jupiter was just a boiling, featureless, fuzzy blob.
Bit of a struggle to focus. Anybody out there imaging it?
There were periods of the night where it was near impossible to tell if focussed or not. Like looking through moving water!
I did try something out of desperation that may (or may not) have worked ok:
Using a bahtinov mask I centred one or more of jupiters moons that were away from the planet and 5sec rolling preview exposures on ASIAIR (evened out some the movement) was able to see diffraction patterns. Adjusted to make symmetrical and then back to the video.
Anyone else tried that before?
There were periods of the night where it was near impossible to tell if focussed or not. Like looking through moving water!
I did try something out of desperation that may (or may not) have worked ok:
Using a bahtinov mask I centred one or more of jupiters moons that were away from the planet and 5sec rolling preview exposures on ASIAIR (evened out some the movement) was able to see diffraction patterns. Adjusted to make symmetrical and then back to the video.
Anyone else tried that before?
Hi David
Generally I slew to a nearby mag 3 or 4 star and use the Bahtinov Mask to focus on the star then slew back to Jupiter.
Remembering to remove the Bahtinov Mask after slewing back is important though. I occasionally forget....