rotation rates tagged posts

Why stars spin down, or up, before they die

Why stars spin down, or up, before they die
Illustration of the inner regions of a massive star during its final oxygen (green) and silicon (teal) shell burning phase, before the collapse of the iron core (indigo). The strength and geometry of the magnetic field, combined with the properties of convection in the oxygen region can cause the rotation rate to speed up or slow down. Credit KyotoU / Lucy McNeill

From birth to death, stars generally slow by 100 to 1,000 times their initial rotation rates; in other words, they “spin down.” The sun’s total angular momentum has declined as material is gradually blown off at the surface as solar wind. By observing this, astronomers have theorized the interaction between magneticfields and plasma flow to be the most efficient way to spin down stars.

Why and how this happens has long int...

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