Main Sequence on the Hertzsprung-Russell Diagram

About 90% of the known stars lie on the Main Sequence and have luminosities which approximately follow the mass-luminosity relationship. The Hertzsprung-Russell Diagram is a plot of luminosity vs temperature, except that the temperature is decreasing to the right on the horizontal axis. The luminosity is noted both in multiples of the Sun's luminosity and in and in absolute magnitude.

Mass-Luminosity Relationship

For main sequence stars, the luminosity increases with the mass with the approximate power law:

The expression uses luminosities and masses compared to those of the Sun.

Sun on Main Sequence

Evolution of the Sun to the Main Sequence

Anticipated Future of the Sun