160,000 light-years away, a star 2,000 times the mass of the Sun is dying. Now, that star has been imaged as never before—extremely up-close—revealing details of the star’s activity and surrounding structure.
The recent image of the star was snapped by the European Southern Observatory’s Very Large Telescope Interferometer, and revealed the way the star is offloading voluminous amounts of gas and dust as it goes through its death throes. Watching how the star offloads that material—and the way that material has stuck around its star—offers details into the end stages of stellar life, as well as details of the star’s system.
The star’s name is WOH G64, offering rare onomatopoeic satisfaction for sounding exactly like what you might say when you see the image for the first time. The star is a red supergiant (like the famous Betelgeuse) and it sits in the Large Magellanic Cloud, a dwarf galaxy that contains some 30 billion stars.
As the star has spat gas and dust into its vicinity, that material formed a cocoon around the star, seen in the below image as a thin elliptical ring. The team’s analysis of the VLTI data was published today in Astronomy & Astrophysics.
“For the first time, we succeeded in taking a zoomed-in image of a dying star in a galaxy outside our own galaxy,” said Keiichi Ohnaka, an astrophysicist at Chile’s Universidad Andrés Bello and lead author of the research, in an email to Gizmodo. “We discovered an egg-shaped cocoon, in which the star is hidden, surrounded with a ring. This means that the dying star is ejecting a lot of material.”
The team chose to image WOH G64 for a couple of reasons. For starters, the supergiant is expelling material at a tremendous rate, cluing astrophysicists into the dynamics of a dying star that is bound to go supernova—to die in a brilliant explosion, ejecting material into the universe. But WOH G64’s distance is also precisely known, making it easier for the team to calculate the mass of the star and the energy emitted by it.
“This star is one of the most extreme of its kind, and any drastic change may bring it closer to an explosive end,” said co-author Jacco van Loon, the director of Keele University’s Observatory, in an ESO release.
“The existence of a dusty torus enshrouding the star was already inferred from earlier measurements, but this time the authors succeeded in actually imaging it, so we can see it properly for the first time, and model its shape and structure, which is an important step in our understanding of this supergiant star,” said László Mólnar, an astronomer at Hungary’s Konkoly Observatory, in an email to Gizmodo. Earlier this year Mólnar co-authored new research on Betelgeuse, positing that the star’s strange dimming pattern may be due to a smaller star orbiting the red supergiant.
“They also see changes in the data and the overall brightness of the star over time, which is fascinating in its own right, but the conclusions are limited by the sparseness of the available data in this regard,” Mólnar added. “I expect that the upcoming 10-year survey of the Rubin Observatory will remedy that issue, too.”
The team intends to take similarly close-up images of the star at longer wavelengths, which could reveal more of the material than in the above photo. Namely, the ring-shaped rejectamenta from the star depicted in the illustration above may become visible in the images of it.
Until then, we’ll have to be satisfied with this eerie, admittedly blurry Eye-of-Sauron-esque very of the red supergiant. But even at such resolution, it’s a wonder that our telescopes can reveal such a distant star up close and personal.
