stellar magnetic fields
Distant star Kepler 11145123 is roundest object ever observed in nature
A team of German researchers has succeeded in measuring the oblateness of a slowly rotating star with unprecedented precision using asteroseismology — the study of the oscillations of stars. The technique was applied to a hot and luminous star called Kepler 11145123 some 5,000 light-years away that is spherical to one part in 500,000.