Jupiter double transit - what could you see?

[Stu]

Having seen Pete's (bunnygod1) excellent image of Jupiter last night, I thought it might be fun to discuss what detail could be seen visually in different scopes.

Pete has kindly agreed that I can post a processed version of his image, trying to represent what I could see visually. It is an inexact science, and I'm not trying to say this is what I saw. In some ways I could see more, and in sharper clarity such as the moons and shadows, but in other ways there are features which I did not see. I'm posting the image as a reference as much as anything.

So, in terms of detail I did see. Europa was clear on the surface of the disk whilst it was nearer the limb. It's shadow was visible all the time (seeing permitting), with the moon itself just clipping into the shadow. Europa disappeared for a time centre disk but reappeared as the limb darkening took effect.

Io was a similar story but to me the shadow was harder to see. The moon was better positioned against a darker belt, but it was overlapping the shadow more so the shadow was presenting as more of a crescent. Europa reappeared so both moons were visible again at sometime after 1am, not sure when.

Other detail I could see included the large festoon and another less obvious coming off the SEB. The NEB showed clear separation with two darker lines to it, one narrower than the other.

The polar regions also showed some detail and I could see the temperate belts, although my Jupiter terminology is not as good as it should be!

I could not see any of the white ovals which are showing in Pete's image in the northern polar regions. Some of the other texture, darker regions along the edges of belts etc was visible though.

I was observing last night with my Tak FC-100 and also a 'mystery' 8" dob which will be revealed in due course ?

The Tak was showing wonderfully stable images, not so affected by the seeing. The detail was impressive for a 4" scope. At times the shadows were harder to see and the moons invisible. I used a Baader Neodymium filter in the Tak but was unable to fit it in the 8" unfortunately, something I will resolve.

The 8" was much more affected by the seeing, the image varied a lot more from poorer than the 4" to much better. When the atmosphere stabilized the views were stunning. The moons themselves were much clearer than in the 4" over the surface, and an extra level of surface detail was visible, very nice indeed.

All in all I would say these were some of the nicest views I've had of Jupiter for a long time, perhaps ever.

Please post up your opinions and let us know what you could see, based on your conditions and scope.

The second image is Pete's original, the first is my attempt to 'de-process' it to a visual representation!

Cheers,

Stu

[Peter Drew]

I was trying out a 20" F3.5 Newtonian Dobsonian lat night on Jupiter around 11pm, long before the transits. The image at best was probably a little better than your processed example using a 11mm TV Plossl giving around 160x, the seeing didn't support a higher power to any useful effect. Still quite pleased with the result for such a "fast" primary mirror. What magnification were you using Stu?

[Paul73]

Like the image Stu. A picture does indeed paint a thousand words.

In my 10" F4.7 SW Dob I could see good detail in the darker southern Equatorial belts but couldn't get the contrast to see the discs against the lighter Northern belt. The shadows were clear in moments of steady seeing.

150x with a 8mm Delos was very sharp but not enough magnification to get moons or shadow.

200x with a 6mm Vixen SLV was the best mag/contrast balance. No filters were used.

Paul

[Davey-T]

I was using the 10"SCT and tried a variety of combo's of 2X Powermate and Ethis 6mm, 13mm and 21mm, I've decided this was my problem, instead of persevering with one thing I hopped about from one to 'tother never settling down to look

Also thought I had a "Jupiter filter" somewhere but couldn't find it so a bit blinded and not helped by the floaters in my eye.

The seeing was not good here but in moments of steadiness the moons and shadows were easily visible depending how they were positioned in relation to the dark bands.
So my view was pretty much as your image Stu.

I'm just amazed that the sky actually cleared in time and conditions were as good as could be expected so couldn't ask for more, sorry I had to pack it in about 1.30.

Took a couple of vid's so I'll see how they look but don't think they'll be as sharp as Petes

Dave

PS: What I should have been doing was trying out the mobile setup ready for SGLX1, haven't tried it since stripping it down 

[Pondus]

Experienced the best Juptier session ever, and timing simply could not be better.

8"dob Fl1200, Baader zoom With barlow 2.25.

My entire Juptier session, in which started maybe 1 hour before the transit, was With 225-338x Power. Absolutely excellent seeing almost all the time.

Main belts was far more colorful than any of the 2 images above. Many variations of Brown, Incredible details. Minor belts alot fainter, but still present. The moment Europatransit began I was surprised how easy it was to see the moon itself, With the shadow so Close by. A tremendous 3D feel. Never seen a Jupiter moon so obvious being a sphere/globe.

Went inside, partly to warm up, partly to see if there was a 'live feed' on SGL (thankfully the where ). 

Afterwards I lost track of Europa, the shadow still being pin Sharp, but I stayed up until Io entered the stage.

Went briefly Down to 150x, got bit tired of nudging the Scope. 150x, which I normally find more than enough to see details on Jupiter, just wasnt enough tonite.

Went back to 338x, and almost tried to physically squeeze out a little extra magnification from the zoom/barlow combo....

My English, and my Jupiter terminology is not good enough to explain the details nor my tremendous adrenalin joy to be one of the very few People on the planet watching this.

 

Rune

PS  I still feel the adrenaline...

[Stu]

1 hour ago, Peter Drew said:

I was trying out a 20" F3.5 Newtonian Dobsonian lat night on Jupiter around 11pm, long before the transits. The image at best was probably a little better than your processed example using a 11mm TV Plossl giving around 160x, the seeing didn't support a higher power to any useful effect. Still quite pleased with the result for such a "fast" primary mirror. What magnification were you using Stu?

Sounds fun ?

I've just done some work to try to calculate the mag I was using. I use a Leica ASPH 8.9 to 17.8 zoom plus a Zeiss Abbé Barlow. I think, given the spacing I was running at, my minimum was x160 and max x320. The best views were between x160 and x200 depending upon the conditions (I tended to stay between x25 and x30 as marked on the zoom which gives a scale but is meaningless in anything other than the spotting scopes the zoom is designed for)

That was in the 8". In the Tak I was towards the top end of the zoom so probably around x180 to x200, perhaps a little more. The Tak coped with higher mag in the seeing, but ultimately the resolution is still lower.

[Stu]

25 minutes ago, Pondus said:

Experienced the best Juptier session ever, and timing simply could not be better.

8"dob Fl1200, Baader zoom With barlow 2.25.

My entire Juptier session, in which started maybe 1 hour before the transit, was With 225-338x Power. Absolutely excellent seeing almost all the time.

Main belts was far more colorful than any of the 2 images above. Many variations of Brown, Incredible details. Minor belts alot fainter, but still present. The moment Europatransit began I was surprised how easy it was to see the moon itself, With the shadow so Close by. A tremendous 3D feel. Never seen a Jupiter moon so obvious being a sphere/globe.

Went inside, partly to warm up, partly to see if there was a 'live feed' on SGL (thankfully the where ). 

Afterwards I lost track of Europa, the shadow still being pin Sharp, but I stayed up until Io entered the stage.

Went briefly Down to 150x, got bit tired of nudging the Scope. 150x, which I normally find more than enough to see details on Jupiter, just wasnt enough tonite.

Went back to 338x, and almost tried to physically squeeze out a little extra magnification from the zoom/barlow combo....

My English, and my Jupiter terminology is not good enough to explain the details nor my tremendous adrenalin joy to be one of the very few People on the planet watching this.

 

Rune

PS  I still feel the adrenaline...

Thanks Rune, glad you got some great views, it really was good wasn't it?

Just to add that I did see colour in my 8", but not appreciably in the 4". Pete's image was mono but I thought it a good place to start for my 'simulation'

[Davey-T]

45 minutes ago, Stu said:

Sounds fun ?

I've just done some work to try to calculate the mag I was using. I use a Leica ASPH 8.9 to 17.8 zoom plus a Zeiss Abbé Barlow. I think, given the spacing I was running at, my minimum was x160 and max x320. The best views were between x160 and x200 depending upon the conditions (I tended to stay between x25 and x30 as marked on the zoom which gives a scale but is meaningless in anything other than the spotting scopes the zoom is designed for)

That was in the 8". In the Tak I was towards the top end of the zoom so probably around x180 to x200, perhaps a little more. The Tak coped with higher mag in the seeing, but ultimately the resolution is still lower.

Damn, forgot to try the Leica

Dave

[Davey-T]

Just been down the obs'y and realised the heater was on, meant to turn it off yesterday morning, no wonder the view was wobbly with all that hot air rising and the scope not cooled 

 

Dave 

 

[John]

Very interesting to see those pics of Jupiter during the transit event

I'm pleased that they seem to confirm my feeling that Io's disk was partially obscuring it's shadow wheras Europa disk was side by side with the shadow it was casting on the cloud tops. I saw a number of the festoons shown in the image in the eq zone and quite a bit of belt structure during the steadier seeing moments. I lost the disk of Europa during the central part of it's transit but I could make out Io all the way across.

I was using my 12" dob at 199x + 237x for most of the event but did have the occasional foray up to 398x to examine the moons and their shadows in more detail.

I wonder what these events would look like to an observer on the cloud tops of Jupiter as the shadows passed overhead ?

 

[bish]

In my 250px I could see the same kind of detail in the North and South, but not quite so much of the equatorial detail (of your picture). When the seeing was excellent for very brief periods I could possibly see some of the finer detail from the original image - mainly in the North and South.  I could see Europa's disc and shadow very clearly, but once Io was in transit the actual planet was very tricky to see, but the shadow was OK.  Seeing was a real mixed bag, on the whole not great but moments of real clarity.

[Pondus]

2 hours ago, Stu said:

Thanks Rune, glad you got some great views, it really was good wasn't it?

Just to add that I did see colour in my 8", but not appreciably in the 4". Pete's image was mono but I thought it a good place to start for my 'simulation'

No Wonders I saw much more color then, eh?

Rune

[Pondus]

Completely forgot to say thanks to @kerrylewis for the heads up on the double transit.

Hope its okay to add in here.

Rune

 

[Stu]

Just now, Pondus said:

Completely forgot to say thanks to @kerrylewis for the heads up on the double transit.

Hope its okay to add in here.

Rune

 

Of course! Thanks Kerry!!

[Davey-T]

Just looked at a couple of vid's, all a bit blurry but was only using the 60Da in crop video mode and 2X Powermate, this is about the least worse
On the other hand it is pretty much how it looked through the eyepiece.

Dave

 

[Special K]

Great idea, Stu, and wonderful to see a pic of this incredible event to compare with my mind's eye!  

Predominantly I was manning the 152mm 'Mortar' frac with 7mm Nagler. I had an early nap and woke fortuitously bang on midnight and began the cooling process. Started viewing about 00:45 with the ED80 and Nagler. Seeing just seemed to improve over the whole course of the session, and Europa's shadow was fairly obvious. But the dark festoons were acting like mirages where I was guessing Io should be. Up to that point I wasn't aware of Io yet and looking at this picture confirms there was a fabulous array of festoons weaving throughout the Equatorial Zone. I gave up guessing and consulted the app. Then I switched to the big scope and Io jumped into view!  Or rather its shadow. No filter used at this point and I was afraid to put in the Barlow and lose prime focus. The marbling at 128x was superb with temperate belts, zones, and the Southern pole region having a much higher degree of color and detail. Then with the Barlow at 257x was fantastic. It was at this point I started experimenting with the color filters and it was when I used the yellow 12 that I realized I could see Europa itself as plain as day!  I didn't pick up on the overlap of moon over shadow though Io's shadow seemed to become more and more rectangular in shape. One struggles with the seeing at times!  But as I distracted myself with Europa about to clear the limb and finish its transit, Io seemed to vanish. I finished watching around 2am as Europa cleared the planet and Io's shadow was coming back into view. At this mag it was pretty sure to see Callisto and Ganymede as discs.

Tremendous session with a rare combination of great seeing and fine transparency. To think I nearly scrubbed the mission because I was down in the mouth about work!!!  

[iPeace]

TV85 with a Nagler 3-6 Zoom. As related elsewhere, I found myself using the zoom as an "alternative focuser" to carefully tweak the image as Jupiter wobbled about; best results varied somewhere between the 5mm and 4mm stops. So not a lot of magnification, as things seem to go (this setup won't go much further, by the numbers), but very pleasing and exiting view. Clouded out for start of Europa's transit, and later could only make out its shadow until it started to emerge from the disk. The start of Io's transit was impressive, and I could follow it for what seemed like quite a while as a white bubble on the planet. Then, for a time I could see neither of the moons, but only their shadows, like two small eyes on a stick figure's head. The latter part of Io's transit showed it as a tiny white bubble again, then a slowly growing pimple and finally detaching into the surrounding darkness. It was of course rather late (read: early) by then, and I cannot discount the fatigue factor. My eyes are also still in the trainee phase, but I am learning to see better . Stu's "visual representation" looks to me more detailed than I actually saw, but I certainly recognize it as what was going on...