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Double Stars

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Spacer The students use the observatory telescope to view three double star systems. They are asked to sketch the systems and indicate which star in the system is brighter and, if possible, note which star is redder and which star is bluer. For each system they are required to answer the following questions and explain their reasoning:

  1. Which star has the greater apparent magnitude and which star has the largest absolute magnitude?

  2. Which star is the more luminous?

  3. From the colors, estimate the spectral class of each star.

  4. Estimate how far away the star systems are.

  5. Assume that the line connecting all stars is perpendicular to the line of sight. What is the physical distance between these stars?

  6. Use the estimated spectral types to estimate the stars' masses. What are the orbital periods of these stars?

  7. Which star has the greatest age and which star has the greatest diameter?

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