Name____________________ Period_____
Earth Science Chapter 30
“Constructing a Hertzsprung-Russell (H-R) Diagram”
Directions:
Plot the data for the stars with asterisks (make sure to do BOTH sides!). You will plot the temperature
in degrees Kelvin vs. the luminosity (i.e. “Go over” to the star’s temperature and “go up” to its
luminosity.).
Analysis:
Label the Main Sequence, White Dwarf, and Supergiant areas of your H-R diagram (Hint: Use page 781 in
your textbook to help you!).
Questions:
1. What Main Sequence color star is the hottest? What Main Sequence color star is the coolest?
2. Define the term luminosity. What is luminosity is the brightest? Dimmest?
3. If a Main Sequence star is hot, would we expect it to be bright or dim? What kind of luminosity
would it have? What color would it be?
4. If a Main Sequence star is cool, would we expect it to be bright or dim? What kind of luminosity
would it have? What color would it be?
5. Define the terms white dwarf star and supergiant star.
6. Explain why a white dwarf star is unusually dim and a supergiant star is unusually bright for its color
compared to its main sequence counterparts.
Extensions:
1. The stars Aldebaran, Altair, Antares, Arcturus, Betelgeuse, Deneb, and Spica were among that stars
you plotted. Name the constellation in which each one appears (Hint: Use page 886-887 in your book
to help you!).
2. An H-R diagram can be used to “see” the lifecycle of a star. List the stages in the lifecycle of a Sunlike star and draw an accurate, labeled picture describing the steps. Do the same thing for a very
massive star.