Jupiter belts?

[vegaandarctures]

I observed Jupiter this morning and I noticed the belts and the zones only appeared If I really concentrate on them. Is this normal?

[Telrad]

hmm, I use a #8 Light Yellow on Jupiter sometimes and it definitely helps bring that colour out.

[Moonshane]

this is probably seeing related. I suspect it may have been quite low in the sky too?

when the seeing is bad or the elevation is low, you are looking through unsettled atmosphere and when low, more unsettled atmosphere than when high.

the trick with planetary observing in particular but also any generally high magnification observing is to watch for longer. as you do, and without moving the focus, you'll see the image shift from sharp to fuzzy to very fuzzy to sharp etc at the seeing 'comes and goes'.

this is normal and the more time you spend looking, the more detail you'll pick out.

all the above assumes the scope is cooled and collimated (which it probably is).

hope this helps.

cheers

Shane

[Moonshane]

ps

you can tell seeing is bad as the main stars really twinkle a lot.

annoyingly very clear or transparent skies often indicate bad seeing (so look at fainter things that require less magnification) and slightly misty or less transparent skies indicate very good seeing (so look at planets, doubles and lunar as faint stuff is likely to be masked by the thin wisps of cloud - this thin wispy stuff can actually make planetary observing better as it acts a bit like a filter).

[vegaandarctures]

Thank you very much!

[Porl]

Thats good info Moonshane, I didnt realise you'd have to just observe for longer to get some good detail. Being a noob I've tried in the past to focus on jupiter and some nights I could get fairly good focus and others I couldnt get any really. When its struggled to focus it could have been poor seeing? And when its been hard to get to focus sharply I've moved on, I should have just looked for longer and more detail would have appeared? cool!

Paul''

[Moonshane]

spot on Paul.

the trick is get the planet as close as you can to a point where it is sharp. I tweak a bit, wait, tweak a bit wait and eventually you'll find the focus point. then leave the focus alone. on average I'd say you get about 10 seconds (spread over the whole minute so a second here and there) of real sharpness every minute and the longer you observe the more detail your brain picks up. when it does go sharp on those good seeing nights, it will make you gasp.

it's strange but true that your brain seems to train itself with more observing and hence why seasoned planetary observers (of which I am not one! (yet)) can often see a lot more detail with smaller apertures than us mere mortals can see with massive apertures.

[astroeddie]

Another good tip is to focus on one of the planets moons. Once they're in focus the planet will be as well.

Good seeing comes with fleeting glimpses. Keep watching, what seems blurry, will suddenly pop out with detail.

With a 76mm reflector you wont get much detail in the belts but, still see the difference in tonal changes.

As Moonshane says, the more you observe the more the eye will see. Sketching trains your eye quickly to note any detail, albedo changes.

Keep us all informed of your next quest.

Eddie

[John]

Where planetary detail is concerned, the saying "the more you look, the more you see" is very applicable. When I was a teenager I borrowed a 60mm refractor and studied Jupiter for night after night for a couple of months, drawing what I saw. The drawings at the towards the end of that period show lots of details as my eye had become "trained" - I've struggled to see that much detail with much larger scopes in some more recent years - of course I've older eyes now as well !.

[Lux1]

One night whilst observing Jupiter last year, there was a brief moment of complete calm it the atmosphere. Only a few seconds, but I went from seeing only one or two faint belts, to seeing several all at once, - at the same moment I thought also just saw the Great Red Storm, then it all seemed to blur up again. This was at about 170x with a 130mm F/5 reflector.