Jupiter was stunning tonight

[markse68]

First time I've been out looking through an eyepiece in quite a long time- I had a quick look yesterday but the seeing wasn't very good but tonight the seeing was excellent. I was treated to a Ganymede shadow transit- an inky black dot, the GRS and a couple of barges (I think that's what they're called anyway) below the lower (northern) belt. In moments of really good seeing there was a lot more detail visible than I remember seeing last year towards the poles which are usually bleached out for me so that little bit of extra altitude seems to really be making a difference. I mainly used a 10mm ep so only 160x or so, and I didn't feel a need to bother with my adc.

Mark

Edited July 18, 2021 by markse68

[Pixies]

Yep - it looked fantastic tonight.

Hopefully we'll get more of this as it rises in the sky.

[PeterStudz]

Yep, I agree. I popped out for a bit and basically saw the same. Saturn wasn’t bad too with surface banding clearly visible and I could see several ring divisions. Not just the Cassini. 
 

And here the last month has been so damn cloudy. Looking up now.

[John]

37 minutes ago, PeterStudz said:

Yep, I agree. I popped out for a bit and basically saw the same. Saturn wasn’t bad too with surface banding clearly visible and I could see several ring divisions. Not just the Cassini. 
 

 

That's interesting. Apart from the Cassini and the gap between the C ring and the planetary disk, I find other divisions really tough to see. I'm thinking of the Encke gap which is really hard to spot. Which ones did you see ?:

 

Edited July 18, 2021 by John

[PeterStudz]

I could just make out the Encke gap, although it would “flick” in and out of view - a second or two now and then. But I could see a difference in colour - eg the A & B. Often, even if I can see the Cassini (and this is new to me) the ring appears as one colour.

This was between 1 & 2 in the morning. 

[Sunshine]

Lucky you! all I've seen for 3 weeks now are clouded over skies 😪

[PeterStudz]

The cloud over the last month has been terrible. I’ve spent a couple of nights in and out of bed hoping that the cloud would clear only to be disappointed and rather tired.

[John]

57 minutes ago, PeterStudz said:

I could just make out the Encke gap, although it would “flick” in and out of view - a second or two now and then....

 

What scope were you using ?

It's a great achievement to get a glimpse of it even with large scopes I believe.

[stuy]

Great seeing here in wales and now I’ve the observatory up and running a great bonus! 3 dark barges in the NEB a big up revival in the equatorial belt too very orangish , and had glimpses of an oval in STB ( zen 12” maksutov  + baader mark v and takahashi 18 mm ortho ) 248x  good of gone a lot higher in mag but at this magnification it was photographic 😳quality 

[Deadlake]

5 hours ago, John said:

That's interesting. Apart from the Cassini and the gap between the C ring and the planetary disk, I find other divisions really tough to see. I'm thinking of the Encke gap which is really hard to spot. Which ones did you see ?:

 

Managed to see Encke gap last Friday night. Didn't know what it was called, so thanks for that.

I did have to use a HR 1.6 mm and 2 mm EP on it to get enough resolution and a goto mount otherwise too  much wobbling going on.

Spent most of the time on Saturn that night as Jupiter was a little too low in the sky.

[John]

1 hour ago, Deadlake said:

Managed to see Encke gap last Friday night. Didn't know what it was called, so thanks for that.

I did have to use a HR 1.6 mm and 2 mm EP on it to get enough resolution and a goto mount otherwise too  much wobbling going on.

Spent most of the time on Saturn that night as Jupiter was a little too low in the sky.

What scope ?

Many report I've seen have folks needing 18 inches of aperture or more to get a definitely sighting of this tiny division.

[Deadlake]

18 minutes ago, John said:

What scope ?

Many report I've seen have folks needing 18 inches of aperture or more to get a definitely sighting of this tiny division.

What I did see was the Cassini division and then another gap in the rings towards the outer permitter, which I was presuming was the Encke division.
Maybe something else, as I can imagine a 4" APO with a 1.6 HR running at 506 x magnification is still not going to see the Encke gap.
What else could it of been? Saturn was framed in the EP with the edge of the rings at the edge of the EP view.

 

 

[John]

25 minutes ago, Deadlake said:

What I did see was the Cassini division and then another gap in the rings towards the outer permitter, which I was presuming was the Encke division.
Maybe something else, as I can imagine a 4" APO with a 1.6 HR running at 506 x magnification is still not going to see the Encke gap.
What else could it of been? Saturn was framed in the EP with the edge of the rings at the edge of the EP view.

 

 

Encke minima perhaps ?:

https://www.cloudynights.com/topic/674315-enckedivision/

 

[Deadlake]

13 minutes ago, John said:

Encke minima perhaps ?:

https://www.cloudynights.com/topic/674315-enckedivision/

 

I'll try with something a little bigger this week and see if I can narrow it down.

Looking through the various divisions in Saturns ring system not many are resolvable with smaller scopes (i.e. less than 11").

Interesting read on CN

Edited July 18, 2021 by Deadlake

[Victor Boesen]

Observing the Encke gap with single digit apertures should be impossible. Calculating the the angular size of the Encke gap tonight, considering it's 325km wide one gets a width of just 0.04998" (arcseconds).
From this information the minimum aperture to resolve this size can be determined, considering one is observing far blue light for highest resolution (shorter wavelength). And with Saturn at its current distance from Earth this aperture is calculated to be 1.916m of aperture....

Doing the same calculations for closest approach on the 1st of August gives a required aperture of 1.91m. This is all theory though, and the Encke gap has been imaged and reported observed through smaller apertures than this, but I doubt anything smaller than 10" could possible resolve the Encke gap. With that said, I'm not trying to argue with what people have observed. I was just curious and did the math for fun

Wish I was out last night but with work at 7AM today I couldn't justify going out... Next time;)