The "color" of the object (I think) doesn't matter. Most of the time, your planetary texture will cover it up. For that, and for many of these such as the atmosphere category, you can put in numbers such as [ 1.0 1.1 0.5 ]. I'm not quite sure if this is correct, but I think the first number in brackets (the 1.0) is the reddish hue of the object, or the amount of red you desire to put in your object if you're creating one. What I mean is, if you look in an astronomy book and look at a telescope such as the Hubble Space Telescope, you can learn that it uses red, green, and blue lenses to create an image of an object in a photograph. This is how I think these numbers in the brackets operate to create your planet color. The scond one, (the 1.1) is the amount of green, and the third one (the 0.5) is the amount of blue. Just play around with different numbers and you'll get different colors.
As for specular color and specular power, they are used to create a reflection on your planet's surface. If you turn on both vertex and pixel shading in Celestia, you'll see a cool light reflection in our earth that will make it look like a plastic ball. For specular color it's the same way as with "color" of a planet. Just insert those numbers in the brackets for the color of the reflection. Speclar power is how bright the reflection is (I think, but I'm not positive). Earth's is 25.0 if you look in the Solar System ssc file.
"Atmosphere { " is just the introductory to your entire atmosphere chunk of information for the planet. "Height" is the height of your atmosphere above the planet's surface in kilometers. "Lower", and "Upper" are the colors of your lower and upper part of the atmosphere, with those bracket numbers again. I'm not quite sure what sky is, but I think it's just the general overall color of the whole atmosphere, with those bracket numbers. You can look in the Solar System.ssc file with notepad or Microsoft Word if you have it, or another reading document, and just look at information for other planets, especially earth. I hope this helps
, and forgive me for making this so lengthy
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