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Stars - Try This!


Try this!

  1. Just like an astronomer, you can learn how to look at a star in the sky and tell something about its temperature. Arrange the following stars in order from hottest to coolest.

    Stars: A is yellow, B is blue, C is red



  2. Though individual stars are difficult to see in another galaxy, one can sometimes see a group of stars. Often stars within a group are the same color which gives a clue to the average temperature of the group.

    Galaxy: A is more red, B is more white

    From the color of these groups of stars, which end of the galaxy is hotter?

  3. Try this outside. On a clear night, look up at the sky. Make sure there are no bright lights and wait twenty minutes so that you eyes can adjust to see faint things. Then count the number of red and blue stars.

    1. Which stars are hotter than the others?

    2. Which group of stars (red or blue) are more abundant?

Adapted from the Star Light, Star Bright activity on the Amazing Space web site.

This activity was developed by Jacqueline Slay, Largo High School, Largo, MD


A service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA/GSFC

NASA Logo, National Aeronautics and Space Administration