Surprising discovery made
First close-up images of stars outside the Milky Way
November 22, 2024 – 5:00 a.mReading time: 2 min.
For the first time, astronomers have captured an impressive close-up of a dying star outside the Milky Way. One detail is particularly surprising.
An international team of astronomers has taken the first close-up view of a dying star outside our Milky Way. The observations of the red supergiant WOH G64 in the Large Magellanic Cloud, about 160,000 light-years away, were made possible using the European Southern Observatory’s (ESO) high-precision Very Large Telescope Interferometer (VLTI). The results, which have now been published in the journal “Astronomy & Astrophysics”, show how the gigantic star sheds gas and dust – a process that brings it closer to its end as a supernova.
“We discovered an egg-shaped envelope that closely surrounds the star,” explains Keiichi Ohnaka from the Universidad Andrés Bello in Chile, lead author of the study, on the European Southern Observatory (ESO) website. This unusual pattern could be related to violent ejections of material from the dying star before it exploded. With a size of around 2,000 solar radii, WOH G64 is one of the largest red supergiants ever observed.
The detailed recording was made possible thanks to a new instrument called “Gravity”, which is one of the most advanced additions to the VLTI. Surprisingly, the researchers found that the star has lost significant brightness over the past decade. “This change is a rare opportunity to follow the evolution of a star in real time,” says Gerd Weigelt from the Max Planck Institute for Radio Astronomy, one of the study’s co-authors.
The unusual shape of the dust cover around WOH G64 raises new questions. The oval structure could be due either to the star’s irregular gas and dust emissions or to the possible presence of a previously undiscovered companion star. ”Such discoveries give us important clues about the final stages of life of stars of this size,” adds Jacco van Loon from Keele University in the UK.
Although the star continues to fade and is therefore more difficult to observe, future instruments such as “Gravity+” open up new opportunities for more detailed studies. “The planned improvements will be crucial to better understand the processes in this extreme star,” emphasizes Ohnaka.
What is the significance of the red supergiant star WOH G64 in astrophysical research?
Interview: Exploring the Discovery of WOH G64
Time.news Editor: Good morning, and welcome to our special segment on groundbreaking astronomical discoveries! Today, we have the pleasure of interviewing Dr. Keiichi Ohnaka from Universidad Andrés Bello in Chile, the lead author of an exciting new study on the dying star WOH G64. Thank you for joining us, Dr. Ohnaka!
Dr. Keiichi Ohnaka: Thank you for having me! It’s a pleasure to be here and share our findings.
Editor: To start with, can you tell us what exactly makes WOH G64 a unique target for your research?
Ohnaka: Absolutely! WOH G64 is a red supergiant star located in the Large Magellanic Cloud, roughly 160,000 light-years away. What makes it fascinating is that it is nearing the end of its life cycle. Our team’s research focused on capturing detailed images of this star as it sheds gas and dust in a spectacular display, ultimately leading to a supernova event.
Editor: That sounds astonishing. You mentioned capturing close-up images for the first time—can you explain the significance of this achievement?
Ohnaka: Yes, this milestone is crucial because it enables us to study the processes that occur during the final stages of a star’s life. Prior to our observations, such detailed close-ups of stars outside the Milky Way were not possible. Using the European Southern Observatory’s Very Large Telescope Interferometer, we could reveal intricate details about WOH G64’s structure and behavior, which can help us understand the life cycles of other massive stars.
Editor: In your publication, you highlight a surprising detail about the star’s shape. Can you elaborate on this egg-shaped envelope you discovered?
Ohnaka: Certainly! The egg-shaped envelope surrounding WOH G64 is unlike any structure we anticipated to find. This gaseous envelope closely hugs the star and presents a unique asymmetrical shape. This discovery raises new questions in astrophysics, particularly regarding how such structures form and what they might mean for the future of the star as it transitions to a supernova.
Editor: It must have been thrilling to observe such a phenomenon! How does this discovery contribute to the broader field of astrophysics?
Ohnaka: This research has several implications. First, it allows us to observe mass loss processes in real time, which is a vital component of stellar evolution. Understanding these processes can help refine our models of how stars like WOH G64 end their lives and contribute to the creation of heavier elements in the universe. Additionally, this study serves as a stepping stone for future observations of similar stars, possibly leading to even greater discoveries.
Editor: Looking to the future, what do you see as the next steps in your research?
Ohnaka: We hope to conduct further observations of WOH G64 and other stars to build a more comprehensive picture of the late stages of stellar evolution. We also aim to combine our findings with data from other telescopes and facilities around the world, expanding our understanding of how these massive stars influence cosmic evolution.
Editor: Fascinating insights, Dr. Ohnaka! Before you go, what would you say to aspiring astronomers who wish to follow in your footsteps?
Ohnaka: Follow your curiosity! The universe is vast, and there are so many mysteries waiting to be uncovered. Stay persistent, ask questions, and embrace the challenges of research—it’s a rewarding journey that can lead to amazing discoveries, just like the one we shared today.
Editor: Thank you for your inspiring words and for joining us to discuss this groundbreaking discovery! We look forward to seeing where this research takes you next.
Ohnaka: Thank you! I appreciate the opportunity to share our work and hope to excite others about the wonders of the universe.