Jupiter: The Oval BA and others

[John]

Excellent seeing conditions tonight enabling my 130mm refractor to tease out some pale oval features in the planets South Temperate Belt. One has been called the Oval BA by regular observers. I can see 3/4 others around it at 240x. Quite hard to spot but they pop into view when the seeing is at it's steadiest.

A couple of nice barges along the north edge of the North Equatorial Belt as well.

These image from Sky & Telescope back in August shows these pale oval features (and barges) along with moon transits happening at that time:

Edited September 23, 2021 by John

[John]

Just an additional note on this. The Oval BA used to be a red coloured storm system, maybe the one sometimes called "Red Spot Jr" ?. It has changed it's colour over the past few years becoming pale / whitish recently. This has attracted the attention of researchers who are trying to work out the reasons for a "Temporal Evolution" of this systems colour.

 

Edited September 23, 2021 by John

[Stu]

Good stuff John. I’ve never had much luck spotting those, must try harder! I’ve had a heavy couple of months but things are settling down a bit now so hopefully from the weekend onwards I can start doing a bit more observing, particularly on Jupiter.

[John]

Just managed to get Neptune's moon Triton with the 130. Rather pleased with that - it's mag 13.4 dimmed to  13.7 by atmospheric extinction according to Stellarium but the limit for 130mm aperture seems to be 13.4 according to the calculators 

I've no doubts that I've picked up Triton visually and it's position corresponds with Stellarium and Cartes du Ciel. Needed lots of magnification - 400x and even 600x used (crazy !!!).

Perhaps Stellarium's estimate of dimming is too pessimistic ?

Anyway, nice to spot Triton with the 5.1 inch scope

 

Edited September 24, 2021 by John

[callisto]

34 minutes ago, Stu said:

I’ve had a heavy couple of months

Painting and decorating Stu 😁

Edited September 23, 2021 by callisto
change wording

[John]

Just a quick bump: anyone else had any luck seeing these white ovals in the southern hemisphere of Jupiter ?

I've noticed them showing quite frequently in images of the planet, mostly when the GRS is on the other side.

I've not had a session with good enough seeing since this thread to pick them out again.

This image from @neil phillips shows them nicely:

 

Edited October 17, 2021 by John

[Deadlake]

Clear sky predicted tonight, I'll see if I can tweeze out the ovals at all. Hopefully I can push over x220...

[Stu]

GRS on show tonight so perhaps the ovals won’t be visible? Tak is out for GRS anyway.

[Deadlake]

9 minutes ago, Stu said:

GRS on show tonight so perhaps the ovals won’t be visible? Tak is out for GRS anyway.

8.03:50 pm next one according to Luminos. 

 

Edited October 17, 2021 by Deadlake

[Stu]

10 minutes ago, Deadlake said:

8.03:50 pm next one according to Luminos. 

 

Where do you see that? Is that a transit time?

[Stu]

@johninderby, you like Luminos, where do you see predictions for Oval BA transit times? 

[johninderby]

In Luminos just select Jupiter, then transits and zoom. While the oval BA aren’t specifically mentioned you can observe the rotation and see when they transit.

 

Edited October 17, 2021 by johninderby

[Deadlake]

58 minutes ago, Stu said:

Where do you see that? Is that a transit time?

it was, missed it as dad duties, but not the best time for seeing, there will be another time...
Next useful GRS Transit is 19 Oct @ 21:42:40. Cloud's permitting.

[Stu]

18 minutes ago, johninderby said:

In Luminos just select Jupiter, then transits and zoom. While the oval BA aren’t specifically mentioned you can observe the rotation and see when they transit.

 

Thanks. Didn’t see Oval BA mentioned. The graphics on these things normally aren’t realistic other than GRS position, is that the case on this too or do they update it so the ovals are correctly represented?

[Stu]

1 hour ago, Deadlake said:

8.03:50 pm next one according to Luminos. 

 

I assumed you were talking about Oval BA transits! I know full well when GRS transits…..

[Stu]

7 minutes ago, Deadlake said:

it was, missed it as dad duties, but not the best time for seeing, there will be another time...
Next useful GRS Transit is 19 Oct @ 21:42:40. Cloud's permitting.

GRS actually looking pretty good tonight, still visible now of course.

[Deadlake]

22 minutes ago, Stu said:

I assumed you were talking about Oval BA transits! I know full well when GRS transits…..

Oval BA is usually 90 minutes ahead of GRS?

[johninderby]

Looks like the Jupiter image is a fixed 3D image and the oval BA don’t seem to rotate at a different speed to the GRS.

Edited October 17, 2021 by johninderby

[Deadlake]

21 minutes ago, Stu said:

GRS actually looking pretty good tonight, still visible now of course.

LZOS on AZ75?

[Geoff Barnes]

I've never seen the Oval BA (I have never heard of it )  but last night with very good seeing I was able to clearly make out twelve distinct colour bands including the polar regions. This was while I was observing the lunar transit of Europa and the GRS across the face. The shadow was lagging slightly behind the GRS as they emerged on the left but gradually caught up with it as they crossed to be together as they exited. Two large dark brown barges (or ovals) above the north temperate zone added interest but not shown on this SkySafari image. Baader Morpheus 6.5mm in the 12 inch Dob gives the premium views... 

 

Edited November 5, 2021 by Geoff Barnes

[alex_stars]

On 24/09/2021 at 00:12, John said:

Just managed to get Neptune's moon Triton with the 130. Rather pleased with that - it's mag 13.4 dimmed to  13.7 by atmospheric extinction according to Stellarium but the limit for 130mm aperture seems to be 13.4 according to the calculators 

I've no doubts that I've picked up Triton visually and it's position corresponds with Stellarium and Cartes du Ciel. Needed lots of magnification - 400x and even 600x used (crazy !!!).

Perhaps Stellarium's estimate of dimming is too pessimistic ?

Anyway, nice to spot Triton with the 5.1 inch scope

 

Hi all,

@John, I am very intrigued by this observation and want to attempt to do the same with my 125mm Apo. I was wondering what you used to get to such high magnifications. Guess you used a barlow? If so which one did work for you.

Another question I had on the Oval BA. Did anybody already figure out how to find transit times on it. Even though Jupiter season is coming to an end at my location I want to get ready to observe it next time round.

Best wishes,

Alex

[John]

1 hour ago, alex_stars said:

Hi all,

@John, I am very intrigued by this observation and want to attempt to do the same with my 125mm Apo. I was wondering what you used to get to such high magnifications. Guess you used a barlow? If so which one did work for you....

 

Hi Alex,

I was using the Pentax XW 5mm. The scope is capable of 300x plus with ease although Jupiter is usually more rewarding in terms of sharpness and contrast (with all scopes) at slightly lower magnifications than other planetary targets.

 

[alex_stars]

Hi all,

if you land here and wonder when to observe the Oval BA, I just made a new thread with transit times:

https://stargazerslounge.com/topic/389474-jupiter-oval-ba-and-grs-central-meridian-transit-times-2022/

Clear skies,

Alex

[Deadlake]

How effective are using BV's to observe Jupiter, would be interested to know? 

I suspect I might need to Barlow them to get enough magnification.

Plan:

• 130 mm/F6
• GPC 2.6 in MaxBright II
• 10 mm UFF 

Thanks

Edited January 20, 2022 by Deadlake

[Stu]

2 minutes ago, Deadlake said:

How effective are using BV's to observe Jupiter, would be interested to know? 

I suspect I might need to Barlow them to get enough magnification.

Plan:

• 130 mm/F6
• GPC 2.6 in MaxBright II
• 10 mm UFF 

Thanks

I think it’s a very personal thing. I still find planetary viewing to be better with a single eyepiece, despite the floaters. I see more detail than with binoviewers. Others report the opposite so it’s hard to say what your situation will be.