Stars How do we find out about them? What would we like to know about stars? Only clues we get are from the light by which we see the stars. The major clues are Brightness Color

Stars What does a star’s brightness tell us? Take two identical stars Put one twice as far away as the other If you compare their brightness, the more distant one will appear four times fainter This one looks brighter Eye

Stars What does a star’s color tell us? Temperature! Reddish star colors indicate a cool star White or bluish colored stars are hotter

Star Colors Can you see a blue star? An orange one?

Stars Surface temperatures of stars Blue-white 45,000 deg F White 20,000 deg F Yellow 11,000 deg F Orange 7,500 deg F Red 5,500 deg F