Dione

General physics and astronomy discussions not directly related to Celestia
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abramson
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Dione

Post #1by abramson » 20.05.2008, 22:10

Ciclops has produced a beautiful new Map of Dione (together with an Atlas) with a resolution of 614m/pixel at the equator.

(I adapted it for Celestia and uploaded to Motherlode, it will be there soon.)

Guillermo

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John Van Vliet
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Re: Dione

Post #2by John Van Vliet » 21.05.2008, 11:07

edit 2:36 pm
Last edited by John Van Vliet on 26.05.2008, 18:36, edited 1 time in total.

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Re: Dione

Post #3by abramson » 21.05.2008, 12:47

Woa, 23k. I'll remove mine from the Motherlode when you prepare this one, John.
G

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Re: Dione

Post #4by BobHegwood » 21.05.2008, 15:46

abramson wrote:Woa, 23k. I'll remove mine from the Motherlode when you prepare this one, John.
G

No reason for that my friend... :wink:
Your current upload looks great! One question though...
Any color data available for this moon?

Thanks, Bob
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Re: Dione

Post #5by abramson » 21.05.2008, 16:21

Ciclops images are not callibrated, so the color is not reliable. Celestia's default color for Dione is reddish, so someone must have found some color information that could be eventually used. I tried but didn't find it.

Guillermo

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Re: Dione

Post #6by BobHegwood » 21.05.2008, 17:53

Well, maybe it doesn't have any color... Hmm....
The best I could find is located HERE.
The quote that goes with the image says it all.
Seen approximately as it would to the human eye, this image of Saturn's moon Dione was taken on 11 October 2005 by the NASA/ESA/ASI Cassini spacecraft.
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Re: Dione

Post #7by abramson » 21.05.2008, 18:28

Yeah, may be. See the same image as captured in Celestia. Supercool. It seems that I need some bue haze in Saturn. Cel url of the same view.

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Re: Dione

Post #8by BobHegwood » 22.05.2008, 01:59

abramson wrote:Yeah, may be.

Can I ask another stupid question here? Thanks... :wink:

How is it that you can still find supposedly realistic reddish images of Dione on the net?
Ain't no wonder us Brain-Dead types are confused about information pertaining to planets and moons.

Can someone please explain to me where the red images came from? Why have I always thought that Dione
was covered with a brownish-reddish layer of dust and some intervening white streaks? I realize that - with
Cassini - some things became clearer, but how did the moon's colors get so screwed up?

Again, sorry to bother but this really bothers me. I am definitely a non-scientist, but I am also someone
who fervently desires realism in my Celestia. :roll: How does this happen?

Can someone explain please?

Thanks, Brain-Dead Bob
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Re: Dione

Post #9by abramson » 22.05.2008, 02:12

As a scientist, I am as upset as you. It has happened with Venus, with Mars, with the moons... Many times it's just that images are taken through narrow band filters, and then reconstructed to something that is only approximately real wide band full color. But I guess other times it's just bad callibration.

I have put the Dione also here. That folder can also be browsed, the png's are there if anybody prefers them over the jpg's.

Guillermo

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Re: Dione

Post #10by John Van Vliet » 22.05.2008, 03:55

edit 2:37 pm
Last edited by John Van Vliet on 26.05.2008, 18:37, edited 1 time in total.

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Re: Dione

Post #11by chris » 22.05.2008, 05:05

Here's the image of Dione that I remember best from the Voyager encounter:

http://apod.nasa.gov/apod/ap951009.html

I have no idea who decided to add the sepia color, or why they decided it would be a good idea. In any case, we really need to update the default textures in Celestia.

--Chris

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Re: Dione

Post #12by John Van Vliet » 22.05.2008, 13:16

edit 2:37 pm
Last edited by John Van Vliet on 26.05.2008, 18:38, edited 1 time in total.

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Re: Dione

Post #13by LordFerret » 23.05.2008, 05:23

chris wrote:Here's the image of Dione that I remember best from the Voyager encounter:

http://apod.nasa.gov/apod/ap951009.html

I have no idea who decided to add the sepia color, or why they decided it would be a good idea. In any case, we really need to update the default textures in Celestia.

--Chris
According to www.solarviews.com -
This image is a color composite of Dione taken by Voyager 1 on November 12, 1980. It was constructed from three separate images taken through orange, green and blue filters. It shows a low resolution view of the trailing hemisphere of Dione. The wispy white streaks are perhaps deposits of snow exuded from fractures in its crust.
http://www.solarviews.com/cap/sat/dionec.htm

See also -
http://www.solarviews.com/cap/sat/dione.htm


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Re: Dione

Post #15by ajtribick » 24.05.2008, 11:06

That makes me wonder about the colouration of other icy moons in the solar system, e.g. the Galileans, the Uranian moons, Triton...

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Re: Dione

Post #16by chris » 24.05.2008, 17:04


It's odd just how monochromatic Dione looks in that picture. To me, that image looks like bad Photoshop work--a composite of a black and white image of Dione with a color image of Saturn. Not that I have any actual doubts about the image, it's just . . . strange.

--Chris

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Re: Dione

Post #17by Hungry4info » 24.05.2008, 18:35

What colour should Dione be? It's my understanding that all of the moons of Saturn, with the exception of Titan, are monochromatic.
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Re: Dione

Post #18by t00fri » 24.05.2008, 18:38

Hungry4info wrote:What colour should Dione be? It's my understanding that all of the moons of Saturn, with the exception of Titan, are monochromatic.

Have a look here:

http://forum.celestialmatters.org/viewt ... 24&start=8

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Re: Dione

Post #19by RVS » 24.05.2008, 18:49

chris wrote:In any case, we really need to update the default textures in Celestia.
I would like to hope very much that this eventual update would also include textures for Earth and Mars! :)

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Re: Dione

Post #20by John Van Vliet » 24.05.2008, 21:49

edit 2:35 pm
Last edited by John Van Vliet on 26.05.2008, 18:36, edited 1 time in total.


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