Learning A Star's True Age, and Kepler's on to it!!

[Suzy]

Kepler is taking the discovery of exoplanets to a whole new level it seems, they are now using it to discover the age of stars....

http://kepler.nasa.gov/news/nasakepl...ews&NewsID=129

“A star’s rotation slows down steadily with time, like a top spinning on a table, and can be used as a clock to determine its age,” says astronomer Søren Meibom of the Harvard-Smithsonian Center for Astrophysics.

Knowing a star’s age is important for many astronomical studies and in particular for planet hunters. With the bountiful harvest from NASA’s Kepler spacecraft (launched in 2009) adding to previous discoveries, astronomers have found nearly 2,000 planets orbiting distant stars. Now, they want to use this new zoo of planets to understand how planetary systems form and evolve and why they are so different from each other.
“Ultimately, we need to know the ages of the stars and their planets to assess whether alien life might have evolved on these distant worlds,” says Meibom. “The older the planet, the more time life has had to get started. Since stars and planets form together at the same time, if we know a star’s age, we know the age of its planets too.”

[astroron (Ron)]

A good find Suzy
This form of finding a Stars age seems so straight forward,but I suppose they have not had the technology until now, with Kepler they can really put it to the test.
Cheers

[renormalised (Carl)]

Yep, gyrochronology. Very useful tool in determining a star's age.

If they're very lucky and have also found some heavy elements in the star's spectra, they can also determine how old they are using the radio-isotopes they find. They've done that with a couple of stars. However, it's not a method that will work with all stars.

[mjc (Mark)]

Very interesting.

But do we need to correlate the spectra features of the evolution of heavy elements (via nuclear transmutation - as Carl suggested), the rotation period as suggested by the presumption of dark spots transiting the stellar disc and the widening of spectral lines due to the Doppler shift to gain more credence of this method?

I think its good news/progress but I'm not convinced at this point that its a break through - but hope that it is.

Mark C.

[renormalised (Carl)]

Originally Posted by mjc

Very interesting.

But do we need to correlate the spectra features of the evolution of heavy elements (via nuclear transmutation - as Carl suggested), the rotation period as suggested by the presumption of dark spots transiting the stellar disc and the widening of spectral lines due to the Doppler shift to gain more credence of this method?

I think its good news/progress but I'm not convinced at this point that its a break through - but hope that it is.

Mark C.

It's just another tool which will help us understand a little bit more about stars. It's a breakthrough in so far as they've not been able to accurately measure a star's rotation rate so precisely. Using this and the rates at which stars brake their rotation as they get older, they can work out how old the star they're observing is.

We use whatever methods we have at our disposal to make the determinations we need to make...so multiple methods will be used.