A new milestone was achieved by the astronomers of the European Southern Observatory (ESO), located in the Chilean Atacama Desert, who, thanks to the extreme sharpness of the Extremely Large Telescope Interferometer (VLTI, for its acronym in English), achieved photograph for the first time a star located in a galaxy outside our Milky Way.
Located at 160 thousand light years from the Earth this star, named WOH G64is specifically found in the Large Magellanic Cloud, one of the small galaxies that orbit the Milky Way. According to scientists, it is a dying starin the final stages of its existence, engulfed in gases and dust before exploding into supernova.
“For the first time, we have managed to take an enlarged image of a dying star in a galaxy outside our Milky Way,” he said. Keiichi Ohnakaastrophysicist at the Andrés Bello University of Chile, through a press release.
Although it had never been able to be photographed, this star has been known for decades by astronomers, who usually call it “the giant star”since it is 2,000 times larger than the Sunbeing classified as a supergianting roja.
“We have discovered a egg-shaped cocoon that closely surrounds the star (…) This may be related to the drastic expulsion of material from the dying star before the explosion of a supernova,” explained Ohnaka, one of the authors of the study, published this Thursday in the journal Astronomy & Astrophysics.
Ohnaka’s team has been using ESO’s VLTI since 2005 to study this giant star, however, it was thanks to the installation of the GRAVITY – second generation instrument capable of capturing light from four telescopes-, who managed to photograph it. And by comparing observations, they could verify that the WOH G64 has gone erasing in the last decade.
“This gives us a rare opportunity to witness the life of a star in real time.”he complemented Gerd Weigeltco-author of the study and professor of astronomy at the Max Planck Institute in Bonn (Germany).
One of the main conclusions of the report is that at the end of their lives, the red supergiants are gradually detaching themselves from their outer layers of gas and dustin a process that lasts thousands and thousands of yearsthose who would be responsible for the overshadowing and cocoon shape that surrounds the star.
“This star is one of the most extreme of its kind, and any drastic change could bring her closer to a explosive ending“, he noted Jacco van Loondirector of the Keele University Observatory (Great Britain), who has studied WOH G64 since the 1990s.
The astronomers responsible for this historic milestone are more than optimistic, since it will soon be ready the GRAVITY+which promises to further improve the sharpness of these astronomical photographs.
“Similar follow-up observations with observatory instruments will be important to understand what is happening in the star”Keiichi Ohnaka concluded.
