First observation of a binary system still with its common envelope

July 8. () –

For the first time, astronomers have observed a locked binary star with an expanding shell of material around it, the remains of the common envelope, key to the development of these systems.

“In the early stages, two stars often revolve around each other without much happening,” he said. it’s a statement Australian National University (ANU) Associate Professor Christian Wolf, lead author of the new research, using images from the Spitzer telescope.

“But when one of the stars becomes a red giant, it doesn’t just claim more empty space like a single star would. Instead, it ‘hugs’ or engulfs its partner, and they appear as a star under an opaque envelope. That’s when things get really exciting. The friction of their movement within the envelope profoundly alters what happens next for the stars. Not only does it heat up, but it slows down the stars, so they spiral into ever tighter orbits; the wrapper eventually overheats and flies away.”

The explosion of the particular binary star observed for the study It happened about 10,000 years ago.

“The common envelope phase is a missing link in the long and complex chain of events that make up the lives of stars. We are now beginning to fix that link,” Associate Professor Wolf said.

“It could even help us better reconstruct gravitational wave events, like black hole mergers.“.

The researchers believe this first glimpse of the phenomenon could lead to the discovery of more stars at this critical stage in their lives.

“It may be easier to recognize them now that we have a clearer idea of ​​what to look for. There may be others that have been under our noses all alongsaid Associate Professor Wolf.

The research has been published in Monthly Notices of the Royal Astronomical Society.