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Blackant
02-10-2009, 10:01 PM
Hi all,

I got very excited tonight as I think I've seen Jupiter's Great Red Spot for the first time. I've been trying since I got my scope but everytime I check with Jupiter 2 to see when it's in view it's either cloudy or past my bedtime :P

I got back inside after having a great time staring at what I thought was it (I think I saw Io's shadow on Jupiter too) but then when I checked some online images of Jupiter, it looks like I was looking in the wrong cloud band :shrug:

The GRS to me looked like it was in the bottom of the two distinct bands around the middle of the planet, not the top one which it seems to be in most people's images :sadeyes:

Was I just convincing myself it was there or do people flip there images :lol:

Confused,

Ant

DavidU
02-10-2009, 10:05 PM
A lot of images are fliped. You can also flip Jupiter2 images.
Images are usually South at the top and E W flip (nach)

iceman
03-10-2009, 06:34 AM
David's right. Most imagers present Jupiter with South Up, which will show the GRS in the top band.

But visually, it may appear in the "bottom" one - depends what type of telescope you're using and how many reflections there are.

Blackant
03-10-2009, 08:54 AM
Thanks Mike and David. I'm using an 8" Dob, which means that the image I'm looking at is also upside down. So doesn't that mean that the GRS should appear in the top band like the photo's?

But I suppose if the imagers are also using a reflector which has an upside down image to start with, then when they flip it the GRS will appear in the top band in the image...my head is starting to hurt :sadeyes:

I suppose my question really is, looking at Jupiter from south of Hobart last night, would the GRS appear in the top main band or the bottom one while using an 8" Dob?

Fingers crossed for the bottom one :D

Kind regards

Ant

Craig.a.c
03-10-2009, 02:19 PM
I have a 12" dob and have seen the GRS many times and it is always at the "bottom".

bird
03-10-2009, 04:20 PM
Your scope will rotate the view 180 degrees, but also remember that you're already upside down since you're looking "north" from the southern hemisphere.

It's a long time since I looked at Jupiter through a refractor, but maybe someone here can confirm that jupiter shows south at the top when viewed from down here.

so using a reflector reorients the view to the natural north-up view.

cheers, Bird

Blackant
03-10-2009, 08:34 PM
Thanks all, yep, I reckon it was the GRS I was looking at, cool :eyepop:

I'd forgotten about the difference between the Northern and southern hemisphere views. It was probably adding to my confusion looking at my Sky at Night magazines (UK ones) that had Jupiter with the GRS in the top band.

regards

Ant