Animation of star plagued by giant magnetic spot

Astronomers using ESO telescopes have discovered giant spots on the surface of extremely hot stars hidden in stellar clusters, called extreme horizontal branch stars. This animation shows what one of these stars, and its giant whitish spot, might look like. The spot is bright, takes up a quarter of the star’s surface and is caused by magnetic fields. As the star rotates, the spot on its surface comes and goes, causing visible changes in brightness.

Note that the movement does not represent the rotation of the star: it mimics the movement of a camera observing the star up close.