Hertzsprung-Russell (H-R) diagram

This diagram is called the Hertzsprung-Russell (H-R) diagram. It shows stars according to their temperature and brightness.

A Hertzsprung–Russell diagram. It shows stars according to their temperature and brightness.

The stars on the diagonal line are in the main sequence stage of their lives.

Question

Our Sun has a temperature of about 6,000 K and luminosity (brightness rating) of 1. Can you find it on the diagram?

Draw a straight line across from 1 on the side ( \text{y}) axis. Draw a straight line up from 6,000 K on the horizontal axis. Where the two lines cross is the position of the Sun.

Question

Our Sun will become a red giant and then contract to become a white dwarf. Can you show this path on the diagram?

Draw a line up to the red giants and then down to the white dwarfs.

Question

Blue giants will become red supergiants as they age. Can you show this path on the diagram?

Draw a line across from the blue giants to the red supergiants.