http://people.csail.mit.edu/jaffer/Color/Heat
	The Colors of Heat

Hot objects can glow visibly. Heat Colors for Blacksmiths shows images of mild steel at various temperatures.

At a given temperature, a blackbody will emit more light than any other surface. The table below shows the colors of a blackbody at exponentially decreasing absolute temperate. The true column of colors is how they would naturally appear. The top color is a sky blue, which has a color temperature of approximately 10000 K.

In the scaled column, each temperature's chromaticity is scaled proportionally to its Celsius temperature. The CIE-L*a*b* column gives L*a*b* values for the scaled colors.

What would it look like if all the chromaticities had the the same luminance?

The y=1 column has the chromaticities scaled so that the y (luminance) in xyz is 1. The black crosses show that all are outside of the sRGB gamut. Scaling each color back so that it doesn't exceed sRGB limits results in the colors in the RGBsat column. The 625 K line was removed because it was identical to the 884 K line.

The RGBsat colors evoke temperature, but in the opposite sense; the cool blue warms up to red hot!

temperature		true	scaled	CIE-L*a*b*	y=1	RGBsat	name
10000 K	9727°C			84.42 03.44 -19.3			heat0
7071 K	6798°C			75.84 02.40 -5.25			heat1
5000 K	4727°C			68.35 03.91 10.86			heat2
3536 K	3263°C			61.14 09.56 28.30			heat3
2500 K	2227°C			53.29 19.86 44.93			heat4
1768 K	1495°C			44.34 32.88 57.39			heat5
1250 K	977°C			34.84 44.75 57.09			heat6
884 K	611°C			25.72 51.87 44.07			heat7
625 K	352°C			17.39 52.37 29.97

The Wikipedia Color Temperature page has a hue graphic similar to RGBsat:

Hues of the Planckian locus, in the mired scale.

The Mired page on Wikipedia says:

Its [the mired scale] use dates back to Irwin G. Priest's observation in 1932 that the just noticeable difference between two illuminants is based on the difference of their reciprocal temperatures, rather than the difference in the temperatures themselves.[2]

Evenly spaced visual differences would be ideal for a Heat map palette. But the reds are too close and don't reach the saturation of heat7:

The table below is a rgb.txt-sytle color dictionary containing the scaled (k), RGBsat (heat), and mired sets of heat-colors.

! Voluntocracy: heat-rgb.txt 2011-11-28
198 210 247		k10000
187 186 197		k7071
182 164 147		k5000
180 140  98		k3536
177 113  48		k2500
169  80   0		k1768
154  41   0		k1250
133   0   0		k884
108   0   0		k625
204 216 253		heat0
242 241 254		heat1
254 229 207		heat2
254 199 140		heat3
254 164  73		heat4
254 123   0		heat5
253  74   0		heat6
254   0   0		heat7
148 177 254		mired0001
205 217 254		mired0101
254 229 206		mired0201
253 193 128		mired0301
254 164  73		mired0401
254 138  21		mired0501
254 116   0		mired0601
254  95   0		mired0701
254  74   0		mired0801
254  53   0		mired0901
254  22   0		mired1001