Earth Sky

First close-up image of a star outside the Milky Way

November 21, 2024
admin


This is the first close-up picture of a star outside the Milky Way galaxy, WOH G64. The star lies in a neighboring galaxy known as the Large Magellanic Cloud, which is more than 160,000 light-years away. The GRAVITY instrument on the European Southern Observatory’s Very Large Telescope Interferometer captured this image. The bright oval is a dusty envelope around the star, which is in the last stages before a supernova. Image via ESO/ K. Ohnaka et al. 

First close-up image of a star outside the Milky Way

On November 21, 2024, astronomers at the European Southern Observatory said that they’ve captured a close-up image of a star in another galaxy for the first time. The star is WOH G64, lying 160,000 light-years away in the Large Magellanic Cloud, a neighboring dwarf galaxy of the Milky Way. Astronomers believe the large oval shape is the dusty cocoon of a star in the last stages of life before it goes supernova.

The astronomers published their findings in the peer-reviewed journal Astronomy and Astrophysics on November 21, 2024.

Lead author Keiichi Ohnaka of the Andrés Bello National University in Chile said:

We discovered an egg-shaped cocoon closely surrounding the star. We are excited because this may be related to the drastic ejection of material from the dying star before a supernova explosion.

The behemoth star

As a matter of fact, astronomers have known about this star for decades and nicknamed it the behemoth star. That’s because it’s a red supergiant about 2,000 times the size of our sun.

So to get this image, the team used the GRAVITY instrument on the European Southern Observatory’s Very Large Telescope Interferometer in Chile’s Atacama Desert. This second-generation instruments captures the light of four telescopes and makes the resolution of the star possible.

By comparing the new, close-up image of the star to previous observations, astronomers could see that the star has dimmed. Co-author Gerd Weigelt of the Max Planck Institute for Radio Astronomy in Germany said:

We have found that the star has been experiencing a significant change in the last 10 years, providing us with a rare opportunity to witness a star’s life in real time.

The star is likely making its last exhalations, expelling the dusty ring and cocoon we see in the image. Co-author Jacco van Loon of Keele University in the UK said:

This star is one of the most extreme of its kind, and any drastic change may bring it closer to an explosive end.

More observations

Of course this the team will make more observations to better understand what is happening with the star. They found the stretched-out cocoon shape surprising, and said it:

… could be explained by either the star’s shedding or by the influence of a yet-undiscovered companion star.

Additionally, the fainter elliptical ring could be the inner rim of a dusty torus, but more observations are needed to confirm that theory.

Bright orange blob at center with darker orange tendrils across the face and in a ring.
Artist’s concept of WOH G64. The main features of this star are its dusty, oval cocoon and dusty ring. Scientists will need more observations to nail down the nature of its egg and ring shapes. Image via ESO/ L. Calçada.

Bottom line: Astronomers have taken the first close-up image of a star in a galaxy outside of our own Milky Way. And this star – WOH G64 in the Large Magellanic Cloud – appears to be getting ready to go supernova.

Source: Imaging the innermost circumstellar environment of the red supergiant WOH G64 in the Large Magellanic Cloud

Via ESO

Kelly Kizer Whitt

View Articles

About the Author:

Kelly Kizer Whitt – EarthSky’s nature and travel vlogger on YouTube – writes and edits some of the most fascinating stories at EarthSky.org. She’s been writing about science, with a focus on astronomy, for decades. She began her career at Astronomy Magazine and made regular contributions to other outlets, including AstronomyToday and the Sierra Club. She has nine published books, including a children’s picture book, Solar System Forecast, and a young adult dystopian novel, A Different Sky.



Source link

Related Posts