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Red Spot transit question

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#1 abaum

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Posted 25 March 2013 - 11:44 AM

Folks,

I am attempting to visually observe the Great Red Spot and so far have been unsuccessful. I am using the embedded web app on the Sky & Telescope website to figure out transit times. Assuming the times listed are correct for my offset, how long should it take before the spot is "centered"? With my scope, I don't think I'll be able to see it when just a portion is visible. I'm using a Vixen ED80sf with 6mm and 12mm Vixen lenses. Pretty hard to make out a number of features in general so the spot sort of needs to be "in my face" for me to see it.

Adam

#2 azure1961p

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Posted 25 March 2013 - 01:03 PM

With that aperture you'd want it all not partial. These days it can be very challenging in that aperture. Poor seeing with my 70 will show everything but the spot.

Pete

#3 blb

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Posted 25 March 2013 - 05:41 PM

The red spot is sometimes a very challenging object. It isn't red but a pale flesh colored spot that is hard to see very far from the central meridian. :gramps:

#4 nirvanix

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Posted 26 March 2013 - 03:11 AM

The Spot flies across the face pretty quickly - only a couple of hours give or take. I would say you've only got +/- 15 minutes from centered to get a good look. If the seeing is decent you'll have an okay view as I recall when I had an 80ed scope.

#5 azure1961p

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Posted 26 March 2013 - 06:26 AM

I think a fair rule of thumb given its difficulty in small apertures is seek it out when its got at least 50% of its spot width separating its following edge from the limb. It does show - but poor seeing can erase it. I used to be able to see it in mediocre seeing at 133x with the 70mm and not that long ago.

Pete

#6 JasonBurry

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Posted 26 March 2013 - 09:31 AM

The spot is very low contrast these days. You can find it by looking for a "bay" in the southern eq belt, rather than the spot itself. Once you find the "bay", the spot will be nestled in it, and will reveal itself if conditions are good.

It's a challenging thing, sometimes.

J

#7 REC

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Posted 26 March 2013 - 09:38 AM

Tomorrow 3/27 at 21:51 the GRS transits. I would say you will need the 6mm in that scope and good seeing to see it.

Good luck!

Bob

#8 HCR32

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Posted 27 March 2013 - 06:26 AM

Don't look for a red spot it's more pink. But at 80mm colour my be a challenge if your eyes are not up to it. You can even try to get more simple eps like orthos or plossl.

#9 nirvanix

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Posted 27 March 2013 - 02:46 PM

GRS will be front and center 8pm Mountain (10pm Eastern) - abaum clear skies to you. :praying:

#10 Tommy5

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Posted 30 March 2013 - 04:23 PM

Any problem with seeing will make it hard to see once you finally see it it is easier to see keep trying a light blue or yellow green filter may make it jump out but your scope has such little aperture it msy not pay to use a filter.

#11 starbux

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Posted 04 April 2013 - 03:26 PM

I use the Freeware program Jupiter 2. Once set up (with your local time and date), you will need to click on the link in the program that takes you to the page that has the current longitude of the GRS. Once that is entered, the program will provide an accurate depiction of the position of the GRS (including where it is in relation to the central meridian as seen by the observer), as well as the Galilean moons.

I've been using Jupiter 2 for several years.






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