Why are stars called main sequence?

1 Answer
Dec 19, 2015

They follow the trend line on the Hertz-Russell Diagram.



These are Hertzsprung-Russell Diagrams (HR Diagrams). The HR Diagram plots a star's luminosity (how bright it is) against how hot its surface is, using the sun as a base for luminosity.

The diagram below plots some well know stars on the sequence.
Most stars follow the main sequence, with bright stars being hot and cool stars being dim. There are a few exceptions, however, the most notable being White Dwarfs, Giants, and Supergiants.

Read more about the HR Diagram here , here, and here.

Read more about the Main Sequence here and here.

Read more about stars in general here.