No detail on Jupiter

[greg110902]

Hi, complete beginner here first night out with my new Skywatcher Evostar 90, and managed to focus on Jupiter n saw 4 moons, which was awesome. But Jupiter itself was only a white ball, and could see some bands, but they were very fuzzy, as if they were out of focus, but I had it as focused as I could. It's been very hot today, could that affect the seeing? The stars don't twinkle too much, but that's pretty much all I can think of, as I believe a 90mm refractor should have enough aperture to resolve detail. Magnification was 180x.  

[John]

Hi, welcome to the forum.

Many are having just the same experiences with Jupiter currently.

The planet is very low so the seeing is affected by viewing through lots of atmosphere.

I've been using my 100mm refractor (Takahashi) on the planet over the past 3 nights and found it equally challenging. 180x is too much magnification really - I've found 120x-140x has given crisper views and shows more surface details than 180x or higher.

So it's not your scope, it's the low position of Jupiter and using a bit too much magnification.

Last night was better in terms of seeing conditions than this evening is for me here, just south of Bristol. Tonight I've stuggled to see much even at 100x.

We need to be patient with the planets at present I reckon !

 

[geoflewis]

14 minutes ago, greg110902 said:

Hi, complete beginner here first night out with my new Skywatcher Evostar 90, and managed to focus on Jupiter n saw 4 moons, which was awesome. But Jupiter itself was only a white ball, and could see some bands, but they were very fuzzy, as if they were out of focus, but I had it as focused as I could. It's been very hot today, could that affect the seeing? The stars don't twinkle too much, but that's pretty much all I can think of, as I believe a 90mm refractor should have enough aperture to resolve detail. Magnification was 180x.  

Hi and welcome Greg.

As John says, the main outer planets (Jupiter and Saturn) are difficult from the UK for the next few years with 2019 and 2020 being about as bad as it gets. The seeing tonight is certainly worse than last night, but it sounds like you made a good start. I can't get Jupiter's moons to settle tonight, they're just continuously going in and out of focus. Your Evostar 90 should yield some decent views in better seeing, but I think x180 magnification is probably going to be too much until the planets gain altitude in a few years time; try dropping down below x150.

Good luck, Geof

[John]

I've just been out again and the seeing is a bit better now. You need to spend quite a bit of time at the eyepiece observing Jupiter to pick out more than the main couple of belts. Just now 125x seems to be working quite well.

If it was higher in the sky, the planet would look quite a lot better and would respond better to higher magnifications as well although very high magnifications never seem to produce good results with Jupiter.

If you have an eyepiece that will give you 100x - 120x try that.

[Mike_S]

For some reason Jupiter wasn’t as sharp for me tonight as last night. Had sharpest view yesterday at X 133

[MarsG76]

Jupiter is one of those planets that needs optimal seeing to resolve maximum details. It can be dissapointing when the seeing is poor but it can also be amazing during the best moments.

As mentioned above, having jupiter low on the sky will hinder what younsee, but ultimately you might just have to view jupiter an number of times until you are at the right time when the atmosphere is very still... Than you will see a amazing sight.

[greg110902]

Thanks all for the replies, this is such a nice community 🤣 think I'm gonna try again tonight if there's a break in the clouds, with my eyepieces I can only get 36x, 72x, 90x, and 180x so I'll probably just start with the lowest, probably like I shoulda last night, and build up to where there's a balance between mag and detail. Can't wait haha, gonna be a long work day

[John]

9 hours ago, MSammon said:

For some reason Jupiter wasn’t as sharp for me tonight as last night. Had sharpest view yesterday at X 133

The seeing last night was not as steady as it was the night before. The night before that it was really poor.

The variable seeing conditions are what dictates what we see and the clarity with which we see it and they are a constant feature of observing in the UK.

One of the reasons that you will see recommendations to observe a target for some time is that the conditions can be constantly changing. Observing over time gives your eye the chance to make the most of fleeting moments of good seeing which is when the detail pops out and your scope shows what it can really do. These moments are what we observe for

[Mike_S]

12 minutes ago, John said:

The seeing last night was not as steady as it was the night before. The night before that it was really poor.

The variable seeing conditions are what dictates what we see and the clarity with which we see it and they are a constant feature of observing in the UK.

One of the reasons that you will see recommendations to observe a target for some time is that the conditions can be constantly changing. Observing over time gives your eye the chance to make the most of fleeting moments of good seeing which is when the detail pops out and your scope shows what it can really do. These moments are what we observe for

This is interesting. I dont know what causes the difference. I got lots of enthusiasm from better conditions the orher night. Observing is more of an acquired skill than I realised which makes it all the more interesting. I dont have interest in processing images so I’m glad I can get better at observing.

[geoflewis]

33 minutes ago, MSammon said:

This is interesting. I dont know what causes the difference. I got lots of enthusiasm from better conditions the orher night. Observing is more of an acquired skill than I realised which makes it all the more interesting. I dont have interest in processing images so I’m glad I can get better at observing.

There are lots of factors that contribute to poor seeing, a significant one of which is the location of the jetstream, which unfortunately frequently passes right over the UK. There are several websites that can provide jetstream forecasts, this is the one that I use.

https://www.netweather.tv/charts-and-data/global-jetstream#2019/06/30/1200Z/jetstream/surface/level/overlay=jetstream/orthographic=-6.72,57.59,712

.... from which you can see that the jetstream is bang overhead today, however, if you play it forward you will see that it is forecast to move clear of the UK again by Tuesday/Wednesday (2nd/3rd July), so let's hope for clear skies then.

Looking back to Friday's (28/06) better seeing, the MetCheck archive shows that much of the UK had the jetstream off to the west, but rapidly approaching, hence a likely contributor to last night's (29/06) less favourable conditions.

http://www.metcheck.com/WEATHER/jetstream_archive.asp

Please note, however, that it is not just the presence of an overhead jetstream that causes poor seeing, but the rate of airflow within in the stream. If there is a constant steady flow even at high speeds, then seeing may still be ok, as it is the boundary layers between different rates of airflow that churn up the atmosphere making planetary observing difficult.

Hope this helps.

Geof

 

[John]

Nice summary Geof

Us UK astronomers have a lot of variables to contend with so all information helps. In a few years the planets will be higher in the sky which will help a lot. Patience is a virtue ...... so they say

 

[ScouseSpaceCadet]

Thurs and Friday for me in NW England there was a definite wibbly wobbly heat haze visible when viewing Jupiter. Last night was a little better. Just keep trying and as the experts have already said, aim for 120-150x mag max.

As another newbie you may not have filters, but I found (and there's current discussion elsewhere here) that using my moon filter to reduce glare (and some chromatic abberation) did tease out a little more detail.

It's worth trying everything at your disposal, however unorthodox, before giving in to mother nature!

 

[John]

27 minutes ago, ScouseSpaceCadet said:

....It's worth trying everything at your disposal, however unorthodox, before giving in to mother nature!

 

Well said mate !

[Cosmic Geoff]

Below is a single-shot or 1-frame image of Jupiter, taken through an 8" SCT fitted with an atmospheric dispersion corrector. Altitude of the planet was ~14 to 15 degrees.

This is what you are likely to see if you take a look at the planet visually. Dire, isn't it?

An experienced observer with patience would see more detail in moments of better 'seeing', especially if observing from a better location.  The blur is caused by observing through an unstable atmospheric soup.  In a vacuum, an 8" telescope would give a much clearer image. 

The frame is from a 5000-frame video which when digitally processed discloses far more detail than shown here.

[Erling G-P]

Been out with my SW 200PDS the last few nights in a row, observing Jupiter & Saturn with an atmospheric dispersion corrector (don't think I've ever had so many mosquito bites at one time before... 🙄).  Jupiter looks remarkably like the image posted by Geoff above, and I've actually found Saturn more rewarding.  Have clearly seen (well glimpsed) the Cassini division in the rings, that the inner part of the rings is brighter than the outer, and have seen a colour difference between the planet & the rings, with the planet more yellowish brown, with traces of cloud bands.  Did require observing for a while, to catch the details in those rare moments when the seeing was best, but it's far better than anything I've seen before, having only observed it with a modest 60mm refractor I got in my teens, some 40 years ago.

With the ADC, I have to use a barlow, as I can't reach focus with the eyepieces alone.  Used an 8mm SWA, which gives 250x magnification with the barlow.  Probably too much, but the smallest at my disposal.

Tried imaging them with a DSLR last night, shooting video, but it was no good - even with the 2x barlow, they're just too small to make anything useful of.

[Stu]

3 hours ago, Cosmic Geoff said:

Below is a single-shot or 1-frame image of Jupiter, taken through an 8" SCT fitted with an atmospheric dispersion corrector. Altitude of the planet was ~14 to 15 degrees.

This is what you are likely to see if you take a look at the planet visually. Dire, isn't it?

An experienced observer with patience would see more detail in moments of better 'seeing', especially if observing from a better location.  The blur is caused by observing through an unstable atmospheric soup.  In a vacuum, an 8" telescope would give a much clearer image. 

The frame is from a 5000-frame video which when digitally processed discloses far more detail than shown here.

Alot depends on the seeing still obviously. Friday night was much better seeing and there was quite alot more detail visible than in your shot Geoff. Other nights have been like your shot, or even worse at times!

[John]

On Friday night I was getting this type of view with my 100mm refractor at 140x:

 

On Thursday night and last night the view was not as good with the same scope. On Friday the seeing was much more settled. 

[Mike_S]

29 minutes ago, John said:

On Friday night I was getting this type of view with my 100mm refractor at 140x:

 

On Thursday night and last night the view was not as good with the same scope. On Friday the seeing was much more settled. 

What eyepiece John? That’s amazing. Was this when it was at its highest in the sky that night?

[John]

10 minutes ago, MSammon said:

What eyepiece John? That’s amazing. Was this when it was at its highest in the sky that night?

It's not an image that I took, it's generated from the Cartes du Ciel software and it is very close to the views that I was getting at that time (10:15 - 10:45 pm) on Friday evening. Jupiter was about as high in the sky as it would get on that evening during that time period - about 15 degrees above the horizon.

The eyepiece was a 7.2 - 21.5 mm zoom used with a 2.25x Baader barlow working at around 6.5mm or so. Not the best quality I've got but very versatile that that counts for a lot when the seeing conditions are so variable.

From the report that Stu posted that evening I think he was getting similar views as well. It was the best of the past 3 nights.

 

 

 

 

[Stu]

13 minutes ago, John said:

From the report that Stu posted that evening I think he was getting similar views as well. It was the best of the past 3 nights.

Yep, that's right. In some ways we did a bit better because this doesn't show the festoons we saw.

[Mike_S]

Yes I had my best view on Friday too which gave me more confidence it was more the conditions than me 

[Greymouser]

57 minutes ago, Stu said:

Yep, that's right. In some ways we did a bit better because this doesn't show the festoons we saw.

This has got me thinking regarding my recent try at observing Jupiter, between the houses on Thursday, with my little C5. I started out with an ES 26mm 62 degree eyepiece and thought, that I was getting a half decent view with several bands/ belts in view. Thing is was I imagining it at only about 48 x magnification? At times I thought I could see more, but was not at all sure. Could I have been seeing festoons at only 48x?

I then tried a Baader Hypeion 10mm eyepiece, ( 125x ) which lost me a lot of detail, dimmer and a lot less sharp. ( I do not think I like this eyepiece at all, it is just not as comfortable to use as the ES. ) Then I tried my cheap Seben zoom, with and without the Baader 2.25x classic barlow, which whilst better than the Hyperion, but was still not showing as much detail, nor as enjoyable as the ES.  The zoom did take it as high as 351x though, so perhaps understandable. at about 8mm and 156x it seemed decent too, better than the Hyperion, but still the ES had it better.

My last question has to be about the ES 62 degree eyepiece, just how good is it considered? Certainly to me it is the best of my eyepieces, budget as I am and certainly better than the Hyperion, but on the scale of quality, where is it considered to stand. I ask because knowing will help me to decide where to go next with regards to my future eyepiece selection.

 

[Geoff Barnes]

Gosh it certainly makes painful reading with what you poor folks are having to contend with up there.

I won't gloat with the views I'm getting down here with Jupiter almost overhead (don't want to get reprimanded by Stu!), but think Astro Avani's images and you're on the right track!

Good things come to those who wait! 

[John]

At lower magnifications festoons can seem like a darkening or mottling of Jupiter's equatorial zone which is where they generally occur.

Most often they are grey / blue loops that come from the southern edge of the north equatorial belt and extend across the eq zone. Occasionally you see them coming north from the south equatorial belt.

Festoons tend to curve as they hit the equatorial zone. Normally I find larger apertures and magnfications in excess of 100x are helpful to pick out the individual festoons from a general darker tone of the eq zone.

Barges and ovals are other features to look out for but those will be challenging from the UK this opposition I suspect. Limb darkening can be more readily observed and this can help to pick out the actual disk (rather than the shadow) of a Jovian moon as it transits the planets disk.

 

10 minutes ago, Geoff Barnes said:

Gosh it certainly makes painful reading with what you poor folks are having to contend with up there.

I won't gloat with the views I'm getting down here with Jupiter almost overhead (don't want to get reprimanded by Stu!), but think Astro Avani's images and you're on the right track!

Good things come to those who wait! 

I've been observing Jupiter long enough to have had such views Geoff. Even last year I got some amazing twilight views of Jupiter with my 12 inch (similar to the above drawing) but it's altitude has dimished this opposition at my latitude to the point where the atmosphere and the gunk that human buildings emit are having a negative impact even when the actual seeing is steady.

Things will improve in due course though - meanwhile please keep reporting your Jovian adventures to keep us keen

[John]

The seeing conditions seem good this evening. I only have my little 70mm refractor out but the detail on Jupiter is surprisingly well defined. 2 main belts and 2 futher belts N and S of those, polar darkening and hints of a couple of festoons coming off the N Eq Belt. Nice