Images from Asteroseismology.org |
All through the galaxy, we find stars that pulsate. Gravity makes stars
spherically symmetric. Because of this symmetry, we can describe the
pulsations with mathematical functions called spherical harmonics. The
patterns of these functions depend on two numbers, usually called the
spherical degree ("l") and the azimuthal order ("m").
The spherical degree changes the total number of hot and cool zones on the surface. The azimuthal order can only be between "-l" and "+l", and changes how the hot and cool zones are distributed on the surface of the star. From a distance, we can only see the brightness of a star change when the spherical degree is small. Play with the values of "l" and "m" to see some of the different ways stars can pulsate. |
Astronomers Discover New Type of Pulsating White Dwarf Star
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. |
Astronomers Discover New Type of Pulsating White Dwarf Star
Images from Asteroseismology.org |
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. |
Astronomers Discover New Type of Pulsating White Dwarf Star
Page created November 10, 2004 by Travis Metcalfe.
Last modified December 22, 2004 by Travis Metcalfe.
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