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Old 08-10-2009, 07:49 PM
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barx1963 (Malcolm)
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Uranus

Finally nabbed Uranus. Tried for it last year and think I got it, but couldn't see a disk so wasn't sure. This time hopped from 96 Aquarii, then slipped in the 13mm Nagler and sure enough, there was a little blue disc. Very excited. Tried the 6mm Plossl and the disc was slightly bigger but FOV was tiny so hard to hold in view. Any way, it was a thrill.

Now to try Neptune!
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Old 08-10-2009, 11:11 PM
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Neptune next ...

Hi Malcolm,

Well done on seeing Uanus the first time . Interesting that you saw it as blue. Don't get me wrong, colour is a very, very subjective thing and its perception varies quite a bit from person to person -- we don't all see colour exactly the same way.

I see you were using 12". In the 10-12" range, I always saw Uranus as yellowish green, though it tends to be darker and more greenish in my 18".

What do others see? What about the colour of Neptune? For me it looks greenish-blue. How is it for you?


Best,

Les D
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Old 08-10-2009, 11:27 PM
Enchilada
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Question Preparation H anyone?

Quote:
Originally Posted by ngcles View Post
Hi Malcolm,

Well done on seeing Uanus the first time
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Old 09-10-2009, 12:26 AM
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Doh !!

Hi Enchilada & All,

What can I say but: Doh!


Best,

Les D
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Old 09-10-2009, 04:47 AM
Enchilada
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Post Uranus Article (11 pages)

I have attached an more general article written on Uranus for barx1963 and others.

It contains some general information abut the planet, moons, and rings. It also includes an ephemeris for 2009 and 2010.

Any comments or suggested improvements would be greatly appreciated.

Hope this is of interest.
Attached Files
File Type: pdf Uranus.pdf (343.0 KB, 27 views)

Last edited by Enchilada; 09-10-2009 at 05:55 AM. Reason: Minor Edit of Document Structure
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Old 09-10-2009, 10:48 AM
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goober (Doug)
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Nice catch - I have found it a few times in various scopes. Definitely looks green to me, while Neptune is a much more blue colour.
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Old 09-10-2009, 11:50 AM
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Quote:
Originally Posted by ngcles View Post
Hi Enchilada & All,

What can I say but: Doh!


Best,

Les D
Freudian slip
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Old 09-10-2009, 12:53 PM
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mental4astro (Alexander)
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Uranus: emerald/lime-green

Neptune: strong sky-blue. Easily distinguishes it from surrounding stars with its vivid colour, with its lack of discernable disk.
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Old 10-10-2009, 07:59 AM
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Uranus appears a pale aqua to me, while Neptune is blue. Will have to check them out tonight!
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Old 10-10-2009, 11:21 AM
Rob_K
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Quote:
Originally Posted by pgc hunter View Post
Uranus appears a pale aqua to me, while Neptune is blue. Will have to check them out tonight!
Yep, that's how I see them.

Cheers -
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Old 10-10-2009, 12:38 PM
StarGazing (Alex)
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I saw Uranus just recently and the color I got was a greenish blue, bit hard to explain. Neptune was definetly more blue.
Alex.
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Old 11-10-2009, 05:01 AM
Enchilada
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Reasoning for the Different Colours of Uranus and Neptune

The colours are matched to the amount of methane in the planetary atmosphere

Methane happens to absorbs much of the faint red-light received from the Sun, which makes Neptune have the richer blue colour.

Uranus has a composition is approximately 82.5% Hydrogen, 15.2% Helium and 2.6% methane.

Neptune is 84% Hydrogen and 15% Helium, with the Methane content being the remaining about 3%.

Uranus appears greener because of the slightly higher temperature of the atmosphere, even though it has less methane. Neptune atmosphere probably also has some more of the colder icy methane.

As I understand it, the chemistry that is happening is not entirely understood, though I remember reading some inconclusive technical paper on experiments in the laboratory.

Regardless, the complex chemistry in the upper atmospheres of these outer planets is likely making the slight colour differences - 'greener' with Neptune'. Combined with the methane being the main contributor of the 'blueness' seen with both planets.
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Old 11-10-2009, 10:31 PM
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barx1963 (Malcolm)
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I guess the colour was probably more aqua, rather than a pure blue. I am planning to try for both Uranus and Neptune at SVAA on the weekend (weather permitting!) so hopefully will be able to provide a definite comparison. Will also be trying pick out minor planet 3 Juno.
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Old 18-10-2009, 04:24 PM
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barx1963 (Malcolm)
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Had a look again at Snake Valley over the weekend. Urnus in a fairly dark sky that we had on Friday night was definately greenish blue. Managed to find Neptune which was just barely a disc with a 9mm (167x) was much bluer than Uranus.
Also nabbed Juno, which was a tiny faint spark. Very pleasing!
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