This H-R (Hertzsprung-Russell) diagram shows 22,000 stars with luminosity plotted versus color. You can see that most of the star plot along a wavy line. These are the main sequence stars.
- The color of a star reveals its temperature.
- 90% of stars are on the main sequence.
- The H-R diagram shows the life cycle of stars and their temperature and color.
With the links below, learn more about main sequence stars. Then answer the following questions.
- Scott Collins The Hertzsprung-Russell Diagram: http://www.youtube.com/watch?v=SvaXfFgrKg4
- Universe Today, Hertzsprung-Russell diagram (webpage): http://www.universetoday.com/39974/
- Which stars are the largest stars?
- Which stars are the brightest, coolest stars? Which are the dimmest, hottest stars?
- If you looked through a telescope and saw a red giant star that was 10 million light years away, what types of stars could it be now and why?
- How do astronomers estimate the distances of star clusters from Earth?