



Look carefully at the diagram. Are all the stars located in one group? Explain you results.
Look at Star A. Describe it in terms of brightness and temperature. Does it make sense that a cool star should be dim?
Now look at Stars B through D. Describe each of them, and see if their brightness and temperature meet the expectation.
Are there any stars that seem out of place?. How might you explain them? Get with your group or neighbors and see if you can propose any solutions. How, for example, might a star be very very hot, but not very bright? What other factors might affect the overall brighness?

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