Spinning Stars Slow Down With Age

Careful astronomical observations of the spin rate of distant stars is revealing their age.
Sunspots on a young star allow observation of their rate of spin (David A. Aguilar - CfA)
Images and data gathered by NASA's Kepler spacecraft have enabled astronomers, including Dr. Soren Meibom from the Harvard-Smithsonian Center for Astrophysics, to determine the age of some stars within a 2.5- billion-year-old cluster.

The new information - including the spin-rate and mass of 30 stars examined - has been compared to what we already know about our own Sun, to help figure out their age. Similar to our Sun, stars spin at a slower rate and lose mass as they get older.

Knowing a star's age is relevant to the search for signs of habitable planets, like the Earth. Those planets will be the same age as the stars they orbit; and life is most likely to exist on planets that are not too old and not too young.

Related Links

- Paper in Nature
Harvard-Smithsonian Center for Astrophysics release
- BBC news story