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Old 04-16-2006, 11:37 PM   #6
dataweaver
 
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Join Date: Aug 2004
Default Re: Space 4e System Generation

I've instituted a "house rule" of sorts for placing planetary orbits in order to simplify the math: any time that orbital position and blackbody temperature interact, I determine orbital position relative to the Snow Line instead of using the star's luminosity. The relationship that I use is:

(orbital radius / snow line radius) = (126 Kelvins / blackbody temperature) squared.

(Why 126 Kelvins? Because that's the temperature that I get when I plug the Snow Line radius into the formula in step 25. I'm seriously considering using 125 Kelvins instead, since it's a nicer number and I doubt that one Kelvin out of 126 will trash the system.)

Step 21, placing a predesigned world: R = (126/B)^2 * Rs
Step 25, blackbody temperature: B = 126 / square root of (R / Rs)
(In both cases, Rs = snow line radius.)

World Type Assignment Table: I pencilled in a column giving appropriate orbital radii as percentages of the snow line radius.

I've replaced the luminosity-based Inner Limit with 0.2% of the Snow Line radius. It requires computing the Snow Line before computing the Inner Limit; but that's not a major problem IMHO.

I'm also inclined to say that not even epistellar gas giants can exist inside the luminosity-based inner limit. Incidently, this also places a hard upper limit of planetary blackbody temperatures: 2800 Kelvins.

I'm looking into guidelines for climate variations based on day vs. night, using the Tide-locked world rules as limits. My problem lies in figuring out how long a day can be before the limits are hit. I'm also interested in computing lattitude-based variations; while I know that there ought to be a simple formula for this, I don't know what it would be.
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