Great Red Spot?

[trevboyd]

My EQ5 drives are off in the hospital, but the clear night last night was too tempting to miss, so I thought I'd spend some time looking at Jupiter. I normally just point the scope at it and have a quick look (and my 3 year old daughter has to have a look too ) before moving on to other things, but I thought I'd have a better look for a change.

I noticed on http://www.skyandtelescope.com/observing/objects/planets/3304091.html that there was a GRS transit at 2226, so I decided to try and spot that. I know that with Jupiter so low in the sky, it would be hard, but figured it was worth a try anyway.

At 125x (24mm Hyperion and 3x barlow in the C8-N), the image kept "swimming" in and out of focus, but just occasionally, it was very clear.

I think I saw the GRS - just occasionally, there was a hint of a slightly darker and larger patch on the "bottom" dark band (sorry - not sure of the correct terms there! ) and it looked like it moved in the right direction as time went on (right to left).

Has anyone else seen it, and does that sound believable?

Thanks!

Trev

[Talitha]

Hi Trev, sounds like you nailed it. The GRS was almost white for a few years and now looks (to me) salmon colored. I find it easiest to locate by looking for a 'separation' in the SEB and then checking in 1/2 hour to see if it moved. Iirc, Jupiter rotates once every 10 hours, so 30 minutes is long enough to show movement.

Btw, the darker stripes are 'belts' (think: brown belt ), and the lighter stripes are called 'zones'. The GRS is in the SEB, or South Equatorial Belt. Here's a labelled sketch of Jupiter showing different features.

[trevboyd]

Thanks, Talitha! That's really helpful, and encouraging to hear it was probably it...

Trev

[John]

I reckon you've spotted the GRS alright Trev

I managed to spot it in my 102mm Refractor a few nights ago. It nestles in a hollow in the SEB and to me the GRS looked slightly paler than the SEB but with suggestions of darkening around the edges of the hollow. It's motion across the disk as Jupiter rotated was noticable as time passed.

It's been tough to see these details this year though - I could barely make out the 2 main belts tonight !!.

John