How is surface temperature represented on the standard H-R diagram's horizontal axis?

Answer

Temperature decreases from left to right

Temperature decreases from the left side (O and B types, hottest) to the right side (M types, coolest). This inverse plotting of temperature is a historical convention.

How is surface temperature represented on the standard H-R diagram's horizontal axis?

#Videos

HR Diagram Explained - Star Color, Temperature and Luminosity

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