Science & Tech · Space · 8 hrs ago
Sakurai’s Object is reheating and blowing a powerful wind
Sakurai’s Object is reheating and blowing a powerful wind after a brief rebirth that began in the 1990s.
The star, in our galaxy, had already stopped burning nuclear fuel when a deep helium layer reignited, making it swell and cast gas and dust into space.
That event briefly made it look like a giant star again, before thick dust hid it from view.
Using the star’s light and computer models, astronomers found bright carbon and helium signals that point to a wind moving about 500 kilometers per second.
The star’s surface has also changed from being mostly helium to a mix with much more carbon, and its reheating is slower than one model predicted.
Because only two stars have been observed during this kind of rebirth, Sakurai’s Object gives astronomers a rare chance to test how stars die.
Sakurai’s Object is reheating and blowing a powerful wind of carbon and helium after a helium layer inside it reignited.
The wind is moving at about 310 miles (500 kilometers) per second, according to the team’s best model.
The star is warming more slowly than an earlier prediction suggested.
Researchers identified bright carbon and helium lines in the star’s light using observations from the Very Large Telescope in Chile.
Sakurai’s Object gives astronomers a rare chance to study a star as it moves toward becoming a white dwarf.
- Who
- Sakurai’s Object, studied by a team led by Wagner Marcolino and Albert Zijlstra.
- What
- The star is reheating and blowing a wind of carbon and helium. It is warming more slowly than an earlier prediction.
- When
- It was spotted in 1996; observations used to confirm the signs of a hot star were gathered in 2023.
- Where
- In the Milky Way. The team used the Very Large Telescope in Chile.
- Why
- A helium layer inside the star reignited, causing it to swell and eject material; it is now reheating as it resumes its evolution toward becoming a white dwarf.
This story does not have two clearly opposing sides.
V605 Aquilae underwent a similar stellar rebirth.
Sakurai’s Object was discovered after brightening following a helium outburst.
Researchers had not found telltale features of a hot star in its light.
Peter van Hoof gathered 18 exposures with the Very Large Telescope.
Several researchers reported faint signs of hot-star features.
- Wind speed
- About 310 miles (500 kilometers) per second in the team’s best model
- Observatory
- Very Large Telescope, Chile
- Observations
- 18 exposures of about 15 minutes each, gathered in 2023
- Surface composition
- Best-fitting model: about 43 percent helium and 51 percent carbon
- Discovery
- 1996
What people are saying
Nobody can see the star itself in a picture, so all they found comes from its light, spread into colors and matched against computer models.