Astronomers from Chile and Germany have captured the first image of the surface of Antares, a red supergiant in the constellation Scorpio. This made it possible to identify rapidly moving clusters of gas near the star, but it is not yet known what exactly sets them in motion. The article of scientists was published in the journal Nature.
Image: K. Ohnaka / ESO
Antares is 555 light years distant from Earth. It is 883 times larger than the Sun, and its size is comparable to the orbit of Mars. To observe the supergiant, astronomers used an interferometer based on the Very Large Telescope, a complex of telescopes installed on Mount Cerro Paranal in Chile. The interferometer works like one giant telescope, which allows high-resolution images of space objects.
Observations of the star were carried out in the infrared range for five days. Data from four telescopes synchronized with each other were processed using a special algorithm.
In addition to surface details, astronomers were able to discern that outside the atmosphere of Antares there are gas clouds moving at a speed of 20 kilometers per second. They envelop the supergiant in a layer 0.7 times the radius of the star itself. Convection - the circulation of matter under the influence of heating and cooling - cannot explain this phenomenon. Betelgeuse, a red supergiant in the constellation Orion, has similar structures, but they move more slowly.