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The Spring 2011 issue of The Earth Scientist is focused on modernizing seismology education. Thanks to IRIS, you can download this issue for free as a pdf. Print copies are available in our online store.

Pulsating Stars

Images from
In our galaxy, we see stars pulsate. Gravity makes stars very round. We can describe the pulsations with math. The patterns depend on two numbers. We call them "l" and "m".

"l" changes the number of hot and cool spots. "m" can only be between "-l" and "+l". It changes how the hot and cool spots move around.

Stars are far away. We see brightness changes when "l" is small. Play with "l" and "m" to see the ways stars 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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The Summer 2010 issue of The Earth Scientist, available in our online store, includes articles on rivers and snow, classroom planetariums, satellites and oceanography, hands-on astronomy, and global warming.

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