Stars like the Sun revolve two and a half times faster at the equator than at higher latitudes, scientists from the University of New York in Abu Dhabi, United Arab Emirates, have discovered – and these findings challenge modern scientific views of the rotation of such stars.
To date, scientists have had little accurate data on the rotation of the sunlike stars, it was only known that their equator rotates faster than the middle latitudes, by analogy with the Sun.
Researchers from the Center for Space Sciences at New York University in Abu Dhabi used the results of observations with the NASA Kepler Space Telescope (Kepler) and astroseismology methods – the analysis of the propagation of sound waves inside stars – to obtain unprecedentedly accurate data on the rotation of sunlike stars .
This study found that the sunlike stars – which are close to the Sun by mass and age – do indeed rotate like our star, in the sense that their equatorial regions rotate faster than the middle and high latitudes. But there is one fundamental difference.
The Sun’s equator rotates about 10 percent faster than the middle latitudes, and the equator of the sun-like stars is up to 2.5 times faster than the middle latitudes of these stars.
“This is a very unexpected result, and it challenges modern numerical models, according to which these stars are not capable of supporting differential rotation of such great magnitude,” said Othman Benomar, research associate at the Center for Space Sciences at New York University in Abu Dhabi, Dhabi and the main author of the new study.
Understanding the differential rotation can help researchers gain a deeper understanding of the magnetic fields of the star, which determine, in particular, in the case of the Sun, the probability of occurrence and the power of flares that cause geomagnetic storms on the Earth, the authors explained.