A red giant's magnetic secret revealed
Astronomers have for the first time measured the shape of a red giant star's magnetic field. Their new method can help explain how our sun will transform itself in a few billion years from now.
A team of astronomers led by Wouter Vlemmings from Onsala Space Observatory and Chalmers, used the radio telescope SMA, Submillimeter Array, in Hawaii to observer the red giant star IK Tau, about 850 light years away.
The star is similar to the sun, but is much older, larger and cooler.
– IK Tau is a bright star that gives us a glimpse of the sun’s future, says Wouter Vlemmings.
The astronomers used light from molecules in the star’s outer layers to measure the shape of the magnetic field close to the star. This is the first time a star’s magnetic field has been measured in this way.
Soon the new huge ALMA observatory, now being built in Chile, will be able to study many other stars in the same way.
- With ALMA we’ll be able to investigate many other stars like IK Tau. That way we hope to find out how stars like the sun evolve and create spectacular planetary nebulae around themselves, says Wouter Vlemmings.
Contacts: Robert Cumming, Onsala Space Observatory, tel 070 49 33 114, firstname.lastname@example.org, or Wouter Vlemmings, Onsala Space Observatory, tel 031 772 55 00, email@example.com
The research paper, “Polarization of thermal molecular lines in the envelope of IK Tau” is scheduled for publication in the journal Astronomy & Astrophysics. It’s already available at http://arxiv.org/abs/1203.2922. The team is Wouter Vlemmings (Onsala Space Observatory and Chalmers), Sofia Ramstedt (Universität Bonn, Germany), Ramprasad Rao (Submillimeter Array, Academia Sinica Institute of Astronomy and Astrophysics, Hawaii, USA), and Matthias Maercker (Universität Bonn and ESO).
Last modified: March 22, 2012
Responsible for this page: Robert Cumming