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The Winter 2010 issue of The Earth Scientist includes a variety of educational resources, ranging from astronomy to glaciers. Check out the other publications and classroom materials in our online store.

# Pulsating Stars

 l = 1 l = 2 l = 3 m = -1 m = 0 m = +1 m = -1 m = 0 m = +1 m = -1 m = 0 m = +1 m = -2 m = -1 m = 0 m = +1 m = +2 m = -2 m = -1 m = 0 m = +1 m = +2 m = -2 m = -1 m = 0 m = +1 m = +2 m = -2 m = -1 m = 0 m = +1 m = +2 m = -2 m = -1 m = 0 m = +1 m = +2 m = -3 m = -2 m = -1 m = 0 m = +1 m = +2 m = +3 m = -3 m = -2 m = -1 m = 0 m = +1 m = +2 m = +3 m = -3 m = -2 m = -1 m = 0 m = +1 m = +2 m = +3 m = -3 m = -2 m = -1 m = 0 m = +1 m = +2 m = +3 m = -3 m = -2 m = -1 m = 0 m = +1 m = +2 m = +3 m = -3 m = -2 m = -1 m = 0 m = +1 m = +2 m = +3 m = -3 m = -2 m = -1 m = 0 m = +1 m = +2 m = +3
##### Images from Asteroseismology.org
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.

#### Shop Windows to the Universe Science Store!

The Fall 2009 issue of The Earth Scientist, which includes articles on student research into building design for earthquakes and a classroom lab on the composition of the Earth’s ancient atmosphere, is available in our online store.

## MOST - Canada's first space telescope

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## A Trip to the Observatory

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## Images & Multimedia

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## The Cosmic Microwave Background Radiation

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## Carina

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## Cassiopeia

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