The best image of the surface and atmosphere of a star that has been obtained so far (not counting our Sun) is the one you have up here. Antares , from the constellation Scorpio.
The image is the result of a team of astronomers, led by Keiichi Ohnaka, from the Universidad Católica del Norte (Chile), which has used the VLTI (the interferometer of the Very Large Telescope of the European Southern Observatory , ESO), installed at the Paranal Observatory , in Chile.
Antares is a huge red supergiant star in the last stages of its life, on its way to going supernova. As Keiichi Ohnaka , who is also the lead author of the article , explains:
During the last half of the century, it has been difficult to know how stars that, like Antares, are in the final phase of their evolution lose their mass so quickly. The VLTI is the only facility that could allow us to directly measure gas movements in the atmosphere of Antares, a crucial step in clearing up this problem. The next challenge is to identify what is driving the turbulent movements.