The SAD3 in space would be nice. However, what if Hubble took a look at the "Sun's Twin" - 18 Scorpii. This star is very close in temperature to the Sun. If it's absorption lines match then it may be another way to get a handle on the Sun's color.

Another possibility, but likely weak in true color accuracy, would be to heat an object close to a blackbody to the Sun's 5700 deg. C temperature. The Sun is not too far off from a blackbody radiation curve in the visible portion. I can't imagine what we would heat-up that would be accurate. I still don't understand the hole in the furnace trick for that matter. It is also possible the Sun's absorption lines would make a difference in the true color afterall.

Therefore, a S.A.D. and a S.A.P. might be the best method afterall.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.