Previously we learned how stars can be studied through the analysis of atomic spectra and their brightnesses. This week we will learn how stars of all types, those like our Sun and those different from our Sun, are born, live their lives and die. The Sun is the closest example of a star and we have learned much about stars by studying the Sun. The Sun can be studied in detail because of its proximity to the Earth. We can readily image features in the Sun's atmosphere and we can monitor those features to study the cycles that govern the Sun's behavior.  As an example of what we can learn, we'll use images to find the Sun's rotation period.   Then we will see how much we can learn about stars in general, even though they are only points of light.

In this lab you will learn about the properties of different kinds of stars and how stars live out their lives. You will learn about
techniques that astronomers use and you will use some of these techniques yourself to determine stellar properties.


  1. Read the background material by clicking on the topics listed on the menu on the left side of this page. For a given topic there may be multiple pages each of which can be accessed using the navigation buttons arranged across the top of each page.
  2. Click on the menu item "Problems". A window should open at the bottom of your screen with the questions.

    Read the section on measuring the rotation period of the Sun very carefully. Follow the outlined procedure and answer the relevant questions on the problems page.
  3. Read the section on HR diagrams. Use the information on the problems page to plot two sets of stars on the HR diagram. Follow the procedure outlined and answer the relevant questions on the problems page.
  4. Read the section on collapsed stellar cores and answer the relevant questions on the problems page.

    Answer the questions by filling in the form fields on the computer. Hit the button labeled "Submit" when you are done. A confirmation page will appear with all your answers imbedded. Be careful not to close the problems window until you are finished and want to submit or your answers may be lost and you will have to reenter your answers.

    Check over the confirmation page to make sure that you are happy with your answers. If you need to change your answers go back to step 6 and re-submit. We will only grade the last form you submit.

    Good Luck!