used by astronomers ESO’s Very Large Telescope Interferometer (VLTI) has taken an enlarged image of the dusty red supergiant star WOH G64.

WOH G64 is located in the constellation Shira, about 160,000 light years away.

The star, also known as IRAS 04553-6825, 2MASS J04551048-6820298, or TIC 30186593, is part of the Large Magellanic Cloud, one of the smaller galaxies orbiting the Milky Way.

WOH G64 is approximately 2,000 times larger than the Sun and is classified as a red supergiant star.

“We discovered an egg-shaped cocoon that tightly surrounds this star,” said Dr. Keiichi Onaka, an astrophysicist at Andres Bello University.

“We’re excited because this could be related to the rapid ejection of material from a dying star before it explodes into a supernova.”

“Astronomers have taken zoomed-in images of and characterized about two dozen stars in our Milky Way galaxy, but countless other stars exist in other galaxies. and were so far away that it was very difficult to observe one of them in detail.

Artist’s reconstruction of the red supergiant star WOH G64. Image credit: ESO/L. Calçada.

Dr. Onaka and his colleagues have been interested in WOH G64 for a long time.

In 2005 and 2007, they used VLTI to learn more about the star’s properties and continued their research in the years since. However, the actual appearance of this star remained elusive.

To achieve the desired photos, it was necessary to wait for the development of VLTI’s second generation equipment. gravity.

After comparing the new results with other previous observations of WOH G64, they were surprised to find that the star had become fainter over the past decade.

Professor Gerd Weigert, an astronomer at the Max Planck Institute for Radio Astronomy, said: “We found that this star has undergone significant changes over the past 10 years, and this is a rare opportunity to witness the life of a star in real time.” he said. .

During the final stages of their lives, red supergiant stars like WOH G64 shed their outer layers of gas and dust in a process that lasts thousands of years.

Dr Jacco van Loon, director of the Kiel Observatory at Kiel University, said: “This star is one of the most extreme of its kind and any dramatic changes could bring it closer to an explosive demise. ” he said.

“These ejected materials may also be responsible for the dimming and the unexpected shape of the dust cocoon around the star,” the astronomers said.

The new image shows the cocoon elongating, surprising researchers who had expected a different shape based on previous observations and computer models.

They believe that the cocoon’s egg-like shape could be explained by the star’s molting or the influence of an as-yet-undiscovered companion star.

As the star dims, it becomes increasingly difficult to take other close-up photos, even VLTI.

Nevertheless, in the future, an update of the telescope’s instruments is planned. Gravity+I promise to change this soon.

“Similar follow-up observations using ESO’s instruments will be important for understanding what is happening inside this star,” said Dr. Onaka.

of the team paper Published in a magazine astronomy and astrophysics.

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Kento Ohnaka others. 2024. Image of the innermost circumstellar environment of the red supergiant star WOH G64 in the Large Magellanic Cloud. A&A 691, L15; doi: 10.1051/0004-6361/202451820