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Pulsating Stars

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All through the galaxy, we find stars that pulsate. Gravity makes stars very spherical. Because of this, we can describe the pulsations with math functions called spherical harmonics. The patterns of these functions depend on two numbers, usually called "l" and "m".

The value of "l" changes the total number of hot and cool zones. The value of "m" can only be between "-l" and "+l". It changes how the hot and cool zones move around the surface.

From far away, we can only see the brightness change when "l" is small. Play with the values of "l" and "m" to see some of the different ways stars can pulsate.

Sounds of the Stars

Astronomers Discover New Type of Pulsating White Dwarf Star

Last modified December 22, 2004 by Travis Metcalfe.

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