Distant star is roundest object ever observed in nature
Stars are not perfect spheres. While they rotate, they become flat due to the centrifugal force. A team of researchers around Laurent Gizon from the Max Planck Institute for Solar System Research and the University of Göttingen has now succeeded in measuring the oblateness of a slowly rotating star with unprecedented precision. The researchers have determined stellar oblateness using asteroseismology - the study of the oscillations of stars. The technique is applied to a star 5000 light years away from Earth and revealed that the difference between the equatorial and polar radii of the star is only 3 kilometers - a number that is astonishing small compared to the star's mean radius of 1.5 million kilometers; which means that the gas sphere is astonishingly round.