Now that you have explored the relationship between spectral type, temperature and luminosity, you can further investigate these variables using with the simple animation at the bottom of the website:

http://astro.unl.edu/naap/hr/hr_background1.html

To check for understanding, use the slider bar to answer the following questions below  .  Answers may be submitted as a text entry or file attachment.

What are the surface temperatures and colors of:

· a hot O2 star?   __________________________

· a cool M3 red dwarf?______________________________

· a G2 star like the sun? _________________________

What is the spectral type of a star with:

· a surface temperature of 10,000 K ?  ______________________

· a surface temperature of 5,000 K ?  _________________________

What is the color of a star with:

· spectral type A0?   __________________________________

· surface temperature 4,000 K?  ________________________________-