2024-09-13 09:18:33
It looks like a giant blackberry, but it’s actually a giant star. Dutch scientists took this amazing photo – here’s why it’s so special.
There are images of our sun that clearly show its bubbling surface. Now, for the first time, scientists have succeeded in depicting the surface of another star in great detail. What is reminiscent of a blackberry are the gigantic bubbles of hot gas produced by the red giant star R Doradus in the constellation of Swordfish.
The images of the star, which is 180 light years away from our Earth and has a diameter 350 times that of our sun, were taken by plasma physicist Wouter Vlemmings and his team from Chalmers University of Technology in Gothenburg, Sweden, using the Alma (Atacama Large Millimeter/submillimeter Array) telescope network of the European Southern Observatory (ESO). They show gigantic convection cells that give the star a grainy appearance similar to a blackberry.
These convection cells, which can be imagined as huge, honeycomb-like clouds, are 75 times the diameter of our sun, the researchers report in the journal “Nature”. They extend over around 105 million kilometers – that corresponds to about two thirds of the distance between the earth and the sun, the experts at “Spektrum” have calculated.
The Alma images taken in July and August 2023 revealed that the distribution of these cells changed significantly within a few weeks. The rapid change surprised the scientists. It shows that the appearance of the giant star is subject to constant changes. With Alma, the events on a red giant could be observed “live” for the first time, says Vlemmings.
In the convection cells of R Doradus, hot gas rises to the surface, cools there and sinks back into the star’s interior at the edges – a process that also takes place on a smaller scale on our sun. However, the convection cells of our sun have an average diameter of only about 2,000 kilometers.
The observations on R Doradus provide valuable insights into how such massive stars function and how they can change over their lifetime – important information for our understanding of the universe and the future of our solar system.