Heads up! Some interesting Jovian moon interactions coming up

[Tulloch]

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.

Here is a presentation I put together for my local astro club, hope you find it interesting.
https://docs.google.com/presentation/d/e/2PACX-1vQ5N35yQyo5FHXAmOzwtSFMPyEeWdyL9OF-G2l2fmUjhQ1TSMn90gZwY8-f2A0DJQ/pub?start=true&loop=true&delayms=30000

Andrew

[Stonius]

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


Cheers


Markus

[Saturnine]

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.

[Nikolas]

Clouds, Clouds everywhere!!!!!

[RB]

Jupiter wouldn't be Jupiter without them Nik.

:)

[redbeard]

So true! Great observation. 👍

[Nikolas]

I see what you did there :lol::lol::lol:

[RB]

Thanks Nik, lockdown...
I’m in a jovial mood...

:lol:

[Nikolas]

Don't you mean Jovian?
(Lockdown v5 down here)

[RB]

Yes, Jovian... :thumbsup:

I know re: Lockdown v5, hang in there :(

[multiweb]

I've been at it since Midnight. The seeing is coming and going. Bit of a struggle to focus. Anybody out there imaging it? How's your sky conditions?

[Dave882]

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.

[Tulloch]

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...

[multiweb]

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.

[Tulloch]

Good luck, take your time :)

[Dennis]

Hi Marc

Well, these are very good and you may just have "saved the day" for this rare event from Australia - great stuff.:):thumbsup:

Cheers

Dennis

[Saturnine]

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.

[Dennis]

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.:shrug:

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.:sadeyes:

Cheers

Dennis

[Dave882]

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?

[Dennis]

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.:sadeyes: I occasionally forget....:rolleyes:

Cheers

Dennis

[pgc hunter]

I was going to head out, but it didn't. Infact, I was going to go to my site and do a big planetary session. Looks like I didn't miss much. I knew the seeing was going to be trash. Ridiculously tightly packed isobars across southern Australia wedged between a low south of Tassie and a high in the bight, and complete Jovian atmosphere-like jetstream casserole above. :rolleyes: A week ago, models showed a big strong high planted smack over SE Australia, but ofcourse we ended up with malarky instead. Tassie had winds of nearly 160km/h. Says it all. :rolleyes:

[kkara4]

It has been a long long time since I posted on the forums, but I have been imaging each year!

I had great success in Brisbane, despite pea soup seeing, which miraculously tidied up just as the transit was ending.

This is a quick single green channel image from my EdgeHD 925 and ASI290MM, 1540.6 UT.

Super stoked with the data I got which I'll process whenever I can this week, and I feel privileged to have seen this, hearing all the reports of unusable seeing or cloud around Australia!

[Tulloch]

Looking very promising!

[RichardJ]

Lots of imaging from Sunday night through to early Monday morning. Seeing was very poor. Had to work today so lots of processing over the next few days. Will post anything decent. Anyway, it was lovely watch the show.

RichardJ :)

[multiweb]

:eyepop: That looks really good. Can't wait to see more. :thumbsup:

[Finbar]

Late to this, but I’m visual, so no images to share.

Having lost the conjunctions of Jupiter-Saturn and Venus-Mars to surgery and foul weather, was determined not to miss this. Chillagoe, FNQ, was the place to be, though cloudy at first, clearing only about 9pm, but winds wrecking seeing for a while. Then it settled, with excellent seeing until near the end. Arrived very late afternoon, with just enough time to check into accommodation and then scout a place outside town to set up the 130mm refractor with Denk binoviewer. Used only the Kson 16.8mm eyepieces.

Callisto was very clear against Jupiter, and its shadow crossing the GRS. Ganymede too, a little less distinct, but outside the occultation could see Europa only as white spot within the edges of Jupiter, but clearly beside Ganymede’s shadow as both neared exit. Also timed Io’s disappearing into shadow and re-emerging. All timings taken to compare against Stellarium when I get home - but having a few days off.

Really excellent experience, making up for bad year, but sorry I can’t share more than verbal description. I really appreciated you photography people sharing images about what I’d missed before.

[multiweb]

Still got to go through a lot of subs but it looks like I might have a sharper one of the contact hopefully.

[Dennis]

Yep - that is a good candidate, you got this on Marc.:thumbsup:

Cheers

Dennis

[multiweb]

Some are good, some are bad but some are pretty cool. 48 footages done, 68 to go. It's going to take me ages. What was I thinking? :lol:

[Tulloch]

You're a good man Marc, nobody else across Australia appears to have been able to get a clear shot of the event...

Pull this off and you could be famous :)

[multiweb]

Nah... I'm already famous for my French crêpes. :evil:
I'm waiting on Krishan series. Those QLDers hogged all the seeing to themselves. :P

[Tulloch]

I'm waiting on Marco Lorenzi in Singapore - he took some exceptional images of a recent Ganymede/Europa occultation, and was right on top of the triple transit/occultation.
https://www.cloudynights.com/topic/783667-mutual-occultations-eclipses-on-jupiter/

Hopefully he will be posting soon...

[multiweb]

He just did. This is insane! :eyepop:
https://www.cloudynights.com/topic/783667-mutual-occultations-eclipses-on-jupiter/?p=11284207

He must have masked the moons to isolate them. Pretty clever trick. You need some serious sampling to do that though.
PS: Oh that was the 8th :lol: My bad.

[Saturnine]

Cristopher Go from the Phillippines has posted some excellent images of the Europa / Ganymede interaction from Monday morning, over on the ALPO website, Jupiter section. Said he had clear skies and steady seeing, has captured albedo features on the discs of the moons as well.

[Tulloch]

Thanks, do you have a link?

[Saturnine]

Sorry for the delay putting up the link to the ALPO, had a golf game to get to . Click on Jupiter in the left hand menu and go the the 15th and scroll through all the images.

http://alpo-j.sakura.ne.jp/indexE.htm

[Tulloch]

No worries, I found this on his Facebook page :)
https://www.facebook.com/100000742388665/videos/2476393859164042/

[multiweb]

That methane filter seems to work quite well to separate the moons from the planet background. And you can still see the shadows clearly.

[multiweb]

Here's my efforts from Sunday night. Bit disappointed with the seeing. Started sort of ok but ended up in pea soup pretty quick. Oh well, good training for the next one. There are a couple of things I'll do differently.


2118-2120UTC (http://www.astropic.net/astro/2118-2120UTC.gif) [276KB]

0024-0213UTC (http://www.astropic.net/astro/0024-0213UTC.gif) [3.7MB]

0239-0348UTC (http://www.astropic.net/astro/0239-0348UTC.gif) [6.5MB]

Added some static shots. Anything after 2:00am was shot in real bad seeing but comparing to the same timestamps in Stellarium it seems legit. You can see Ganymede going in front of Europa then Europa re-emerging bright then eclipsed again but by Ganymede shadow then re-emerging. By then it's pea soup territory and at 40 degrees elevation westwards. It's a real shame. I hope Marco got something super sharp.

[Dennis]

Hi Marc

I enjoyed watching those animations, #2 in particular was excellent for the conditions.:thumbsup:

You still managed to resolve details on the satellites of Jupiter which is quite an achievement given the seeing conditions you endured.:)

I think the extra 6.6 sq cms aperture area of the 212 over the 210 really helped.;)

A lot of hard work, both outdoors and indoors, but it has given you a good record of this rare event.:)

Cheers

Dennis

[multiweb]

hmmmm.... looks like I reversed the animation and the times are all wrong. :rolleyes: I have to check stellarium see what I did. My timestamps must be wrong on my lappie again.

[Dennis]

Hah, I was too enthralled watching to notice anything.:)

Cheers

Dennis

[Saturnine]

[QUOTE=multiweb;1530795]Here's my efforts from Sunday night. Bit disappointed with the seeing. Started sort of ok but ended up in pea soup pretty quick. Oh well, good training for the next one. There are a couple of things I'll do differently.


Great animations Marc, love them. Considering the conditions, you've done well.

[Dave882]

Great work Marc! Some good captures in there thanks for sharing!!

[multiweb]

Thanks guys. :thumbsup: All fixed now.

[Dave882]

It's pretty rough- but here's the full night 15-16th August 8:15pm - 4:45am (warts and all) animated! Better late than never right?

A bit of an epic task made very difficult by the lack of decent data, and I don't have the post processing skill to make it any prettier unfortunately - but i feel you get a bit of an idea of what it was really like on the night!! Final product probably not exactly how I'd envisaged but it was certainly a unique experience! The kind of thing you'd only ever do in the middle of an indefinite lockdown i suppose...

Full Animation HERE (https://1drv.ms/u/s!ArpSiLT3VkGHiO9KtDasqUCVBPSkMQ?e= vcY02T)

Also did a separate animation of Europa moving OUT/IN of Ganymede's shadow HERE (https://1drv.ms/u/s!ArpSiLT3VkGHiO9JEz4ARErlh5Bl6A?e= 54t8mQ)

10" LX50 on CGEM
ASI224mc - 1.8 Barlow - UV/IR Cut
ASIAIR Pro (60sec vids @ 5min(ish) intervals)
AS!3
Registax6
PIPP

Thanks for looking!
Dave

[Tulloch]

Great job guys, lots of processing time has gone into these :)

[Finbar]

Thanks Dave.
Beautiful reminders of what I watched.

I do admire you astrophotographers, but think it takes a particular form of lunacy to do that type of work. Feel free to correct me. I really don’t have the time, and generally rely on a very good visual memory (autistic gift), but do regret not being able to share what I watched.

[Dave882]

Yep lunacy indeed!! To be honest (and if the conditions permit) I actually enjoy the visual more and I had the dual setup on Sunday night with binoviewers on a second scope. I think for me it was more about setting myself the challenge of learning a new skill during lockdown. I’m not trying to be the best but it is cool to have something to share with friends/family afterwards!

[multiweb]

Visual is one thing but imaging you can go deeper, sharper, see colors and keep a record. It doesn't replace visual but it complements it. There is also the technical/tinkering side of things with the gear and of course the processing that comes with imaging. It's the whole package. There's a bit for everyone in it.

[multiweb]

You guys probably know that but there is another Ganymede/Europa occultation Sunday night against the sky background this time well positioned @ 64degrees. Forecast is very iffy here in Sydney with possible rain but I'm so desperate that I'm even contemplating using an umbrella. :lol:

[Saturnine]

Also followed by an double shadow transit of Europa and Ganymede about 4:00 to 6:00 am Monday morning. It may clear but , like last weekend, the jetstream wont be doing us any favours unfortunately. Will be looking anyway to see if it is worth imaging .

[Dave882]

Can I ask how you guys get reliable forecasts for the jet stream? And how far out can it be predicted?

[multiweb]

http://www.bom.gov.au/australia/charts/viewer/index.shtml?type=windbarb&level=200hPa&tz=AEDT&area=NSW&model=R&chartSubmit=Refresh+View

About 2 days ahead.

[Dave882]

Thanks Marc that’ll be very helpful

[multiweb]

All pred for tonight. Fingers crossed.

[Dave882]

How’d you go Marc? I had a quick look about 10-12pm and the seeing was quite poor, then the clouds rolled in for a bit, then it started spitting rain. That was it for me. I did poke my head out a bit later and the clouds had partially cleared but didn’t have it in me to set back up…

[Tulloch]

We got dudded again down in Melbourne - strong winds, thick clouds with just a couple of small holes to keep me out there. I got a few images of the moons approaching, but then it all clouded over and the moment was lost :(

[multiweb]

Well last night was clear here and almost perfect if it wasn't for the seeing which got very bad after 23:00. It wasn't too good to start with but surprisingly had room to degrade much further. Apart from that it was perfect. Dry and quite warm. No wind and good transparency up ahead. I could smell and see smoke out west but it wasn't an issue. Did about 100 x 45s segments of 7000 frames. Still have to go through the data.

Anybody out last night? Any success?

[multiweb]

:eyepop: I saw some lightning in the direction of Richmond but no rain here.



Damn. Maybe you get better luck tonight. There's another interesting event. Here high wind and rain starting this arvo so last night was the last.

[Dennis]

I think I saw the satellite eclipse event on the FireCapture Recording display as I was recording a SER on the Notebook, but then the clouds rolled in so I'll have to see what I ended up with.

The seeing was okay for the satellites, but not up to scratch for the Jovian disc.

Cheers

Dennis

[multiweb]

Good stuff. Can't wait to see. :thumbsup:

While I was focusing on Saturn last night I saw something zooming past the fov in front of it but I wasn't recording. I thought bugger. I had been recording non stop for 10min prior and just when I focus something interesting happens. :question: That made me remember Anthony Wesley told me a while ago that you can have a buffer set in firecapture for things like this. That you can go back to. You wouldn't know about that? One year later I forget all about UTC timestamps what are the odds I'd remember something like that. :lol:

[Dennis]

Okay, here is the best of the bunch as we had banks of clouds that drifted through which played havoc with the recordings.

This one was taken between sets of clouds at 00:18:16 am AEST.:)

You can see by the general softness of the Jovian disc that the seeing was variable. I can also see diffraction patterns around the point-source like satellites.

The inset is a x1.3 up sample of the Ganymede Europa pair overlaid in PS CC.

Tak Mewlon 210 F11.5, Tele Vue 2" PowerMate x2 and ASI 462 MC camera.

Cheers

Dennis

EDIT: Just added another image, time stamped at 00:1345, some 5 mins earlier than the original, showing a slightly larger crescent for Europa.

[multiweb]

That's awesome mate. :thumbsup: Even got details on the moons.

[multiweb]

Bit disappointed with the conditions but here's what I got: http://www.astropic.net/astro/occultation_20210822.gif

Ganymede up top Europa coming from the bottom. Jumps are missing segments from clouds. Seeing was terrible so it wasn't straight forward to process but you get the idea. :)

[Dennis]

Very nice Marc, who'd have thought, a few short years ago, that amateurs, with modest equipment but extraordinary talent and dedication, would have been able to achieve such animation results. :)

I stayed at a lowly 4800mm FL and this is the best of the bunch so far from Brisbane.:)

Cheers

Dennis

[Dennis]

Hi Marc

I am going to give up imaging these events.:sadeyes:

Have a look here:

https://www.cloudynights.com/topic/785607-2021-08-22-eclipse-and-occultation-of-europa-by-gynamede/#entry11313400

Awesome animation.:)

Cheers

Dennis

[multiweb]

:eyepop: Perfect seeing. Heaps better than my two slimmy amoebas going at it. Got another 6 years to get a bigger scope :lol:

[Dennis]

I just threw all my 1/2 decent files into Images Plus for an Auto Planet Align and produced this composite, using a Jupiter from a previous session.

The variations in brightness of the moons and gaps in their orbits are the result of bands of clouds passing through during the capture session.

Cheers

Dennis