Red supergiant (RSG) stars are considered the most voluminous stars in the universe. The two most famous examples of RSGs are Betelgeuse and Antares, and to the naked eye the latter appears to shine with a strong red tint as it sits at the heart of the constellation Scorpius. However, RSGs are known to exhibit a certain kind of behavior that's baffled astronomers for a long while.
A team of astronomers decided to figure out this strange phenomenon by taking a closer look at Antares, a star already at near the end of its life. "How stars like Antares lose mass so quickly in the final phase of their evolution has been a problem for over half a century," Keiichi Ohnaka from the Universidad Católica del Norte in Chile and lead author of the study said in a press release.
His team used the Very Large Telescope Interferometer (VLTI) of the European Southern Observatory (ESO) at the Paranal Observatory in Chile, with which they mapped the surface and movement of the surface material of Antares. The result: they managed to take the best image of an extra-solar star's surface ever. Their research has been published by the ESO.
This was made possible by the VLTI's ability to combine light from four of its telescopes to create a virtual telescope that works like a single mirror that's 200 meters across. It, in turn, allowed the team to recreate a two-dimensional velocity map of a star, the first such beyond our solar system.