The mapping of the magnetic field of TX Camelopardalis can provide important insights into the behaviour of stars
the magnetic field of a star has been mapped for the first time by a team of researchers at the National Radio Astronomy Observatory, usa . The team led by Kemball and P Diamond has mapped the magnetic field of tx Camelopardalis ( tx Cam), a red giant star about 100 light years away. A giant star is one with a relatively large radius. The brightness of such stars is high as the radiating area is correspondingly large ( Astrophysical Journal Letters , Vol 487 No 2).
As the magnetic field of a star cannot be observed directly, the researchers used radio waves, which are polarised by magnetic fields, to map it. Radio waves from the stars that are at a great distance from the Earth are too faint to be seen.However, in this case, the radio waves could be detected because of the presence of clouds of silicon monoxide near the star, which amplified the signals.
The researchers used a network of 10 radio telescopes stretching across the us . This network, known as Very Long Baseline Array, achieves unprecedented resolution because it operates like a single telescope with a dish size equal to the size of continental usa. By observing the polarisation of the radio waves, the scientists have been able to get a two-dimensional map of the magnetic field of the star.
They claim that the field is very much like that of the Earth with lines going around the star. Nevertheless, there are also some areas where the field lines are twisted. The first detailed map of the magnetic field of a star could provide important insights into the behaviour of stars and also throw light on stellar formation. Kemball and his team plan to observe the star perio-dically to ascertain if there is any temporal cycle associated with the magnetic field.
We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.
Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.