Jupiter 18/11/11 spot?

[mcro89]

Hey all,

I have just been out to have a look at jupiter with my 150p and i could see a dark spot on one of its bands, at first i thought it was the great red spot but when i looked on stellarium at the same time i was observing there is nothing there?

Anyone confirm what it was? was it just another storm spot? I was observing from 19:00 - 19:30.

I have only ever seen the two bands through my scope, this was the first time i have seen a bit more detail.

Cheers

Matt

[Stu]

Hi Matt

My phone app is showing the GRS as visible now, transiting the meridian in about half an hour. If what you are seeing is pale and quite large then most likely the GRS. If it is quite small, dark and more oval in shape then it is probably a barge. Barges are, as far as I recall, shorter lived storms, normally in the northern belt at the moment.

If you are seeing a barge, try for the GRS as it should be there!

Hope that helps

Stu

[mcro89]

I shall have a quick look now

I made a sketch which i will put up here once i have scanned it in, I believe it was in the northern belt (if my sense of north and south are correct).

Anyway I have set my scope up as it will be clear all night, i will popping in and out. The main target will be mars a bit later.

Cheers

[mcro89]

I see now,

I can now see the GRS in the southern band (wow!), there is still a darker spot on the northern band just about to go out of view.

These are some of the most detailed observations i have done, as i said before i have only just made out the north and southern bands before now and i have been looking at jupiter for a good few moths now.

Thanks Stu for your help

[Stu]

Excellent, well done!

In a newtonian, I think the image is inverted so the GRS will appear in the top belt which is actually the Southern one. There are quite a few barges in the northern belt which are often easier to see than the GRS. It's great to see them all transiting, with the barges at a different rate to the GRS.

Keep watching and you will catch the detail in periods of good seeing.

Also, check on stellarium for moon transits, the shadows show up very clearly on the surface of Jupiter so are good to watch

Cheers

Stu

[mcro89]

Hi Matt

My phone app is showing the GRS as visible now, transiting the meridian in about half an hour. If what you are seeing is pale and quite large then most likely the GRS. If it is quite small, dark and more oval in shape then it is probably a barge. Barges are, as far as I recall, shorter lived storms, normally in the northern belt at the moment.

If you are seeing a barge, try for the GRS as it should be there!

Hope that helps

Stu

Oh yea I forgot to ask, What phone app do you use?

Cheers

Matt

[Stu]

Hi Matt

I use an android phone, samsung galaxy S and there are loads of apps available. There are plenty of threads on SGL covering what's available.

The specific one I use for Jupiter is called Galilean, on the market. It shows the position of the galilean moons and transits/shadow transits. It also shows the position of the red spot so is very useful. Another favourite of mine is Mobile Observatory.

Note that the red spot moves so you need to have the correct position for it in order to get the predictions correct. I have it set to 168° which I think is correct. This may also be the reason your stellarium was not showing it the other night. Not sure how to fix in stellarium but again, there are a couple of threads on here discussing it.

Hope that helps

Cheers

Stu