Exercise

  1. Open the spectrum of your observed star.  
  2. Are there any spectral lines in your star?  If so, are they absorption or emission lines?  Can you identify any of these lines as Hydrogen?
  3. Are you able to easily identify the white light peak in your spectrum?  If so, calculate the temperature of the star using Wein’s law.  If not, explain why it is difficult to determine the peak wavelength needed for Wien’s Law.
  4. Compare your spectra to the other groups in the class.  Describe the differences between the spectra of hot stars and cool stars.
Spectral Sequence

Your instructor will provide each group with a spectrum of different star. These stars will each have a different spectral classification (O, B, A, F, G, K, M).  The goal of your group will be to describe your own spectrum so that the class can combine the data to observe the changes of stellar spectra with spectral type.