Planckian locus

Locus of colors of incandescent black bodies within a color space

In physics and color science, the Planckian locus, or black body locus, is the path, or locus, that the color of an incandescent black body would take in a particular chromaticity space as the blackbody temperature changes. It goes from deep red at low temperatures through orange, yellowish, white, and finally bluish white at very high temperatures. A color space is a three-dimensional space; that is, a color is specified by a set of three numbers (the CIE coordinates X, Y, and Z, for example, or other values such as hue, colorfulness, and luminance) which specify the perceived attributes of a particular homogeneous visual stimulus.

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