Can somebody tell how Celestia is calculating the effective temperature of surfaces?
I assume that the "Stefan-Boltzmann-Law" is used. With what solar constant? -> 1368 W/m^2 ?
Shouldn't Celestia calculate a value of 255 K (instead of 257 K) for Earth?
Adirondack
Calculation of temperatures in Celestia
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Topic authorAdirondack
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Calculation of temperatures in Celestia
We all live under the same sky, but we do not have the same horizon. (K. Adenauer)
The horizon of some people is a circle with the radius zero - and they call it their point of view. (A. Einstein)
The horizon of some people is a circle with the radius zero - and they call it their point of view. (A. Einstein)
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Chuft-Captain
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Celestia takes into account global warming. 
Sorry (not trying to be at all helpful)
Sorry (not trying to be at all helpful)
"Is a planetary surface the right place for an expanding technological civilization?"
-- Gerard K. O'Neill (1969)
CATALOG SYNTAX HIGHLIGHTING TOOLS LAGRANGE POINTS
-- Gerard K. O'Neill (1969)
CATALOG SYNTAX HIGHLIGHTING TOOLS LAGRANGE POINTS
Celestia takes into account the albedo, in the temperature calculation. Since Earth reflects some light, its temperature is a bit lower than what we get with the black body formula alone. This explains the small difference you noticed.
Celestia doesn't take into account the atmosphere effect (warming, etc), since it heavily depends on the chemical composition, gravity, rotation, etc.
Celestia doesn't take into account the atmosphere effect (warming, etc), since it heavily depends on the chemical composition, gravity, rotation, etc.
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"
255K or 257K, these are very cold temps! 257 is almost 18 degrees below freezing. I thought the figure would at least be above freezing..
BTW, the temperature of planets in Celestia is indirectly computed from the Sun's temp. Planet_temp = sun_temp * sqrt(sqrt(1 - albedo)) * sqrt(r_sun / 2*D) where r_sun=sun's radius, D=distance from sun.
BTW, the temperature of planets in Celestia is indirectly computed from the Sun's temp. Planet_temp = sun_temp * sqrt(sqrt(1 - albedo)) * sqrt(r_sun / 2*D) where r_sun=sun's radius, D=distance from sun.