English: Theoretical Planck-model "white-sun" ternary plot for visible-light color-temperature from left to right between 500°C (the temperature around which objects begin to glow in the visible) and 6000°C (slightly more than the color temperature of the Sun) with intervals of size 500°C.
The next two intervals represent changes by 2000°C, with the blue dot to the right of the first large gap corresponding to 8,000°C, followed another at 10,000°C. The next to last dot rightward is at 20,000°C, with the far right dot near {R,G,B} ≈ {0.12,0.23,0.65} representing the zero-coldness 1/kT (i.e. infinite-temperature) point.