Turkish scientists discover star system, challenging formation theories

ISTANBUL

Researchers at Istanbul University and Akdeniz University have made an important discovery about the CN Lyn star system. Unlike most multi-star systems, CN Lyn's three stars formed at different times, contradicting current star formation theories.

The research, supported by the Scientific and Technological Research Council of Türkiye (TUBITAK) and Istanbul University's Scientific Research Projects Coordination Unit (IU BAP), combined data from space telescopes TESS and Gaia with observations from ground-based telescopes.

The team found that the CN Lyn star system originated at the edge of the Milky Way’s disk, with the third star later joining from the galactic halo.

This breakthrough challenges conventional theories of how stars form, showing that not all multi-star systems follow the same creation process.

CN Lyn formed in unexpected way

Professor Selcuk Bilir from Istanbul University explained: "While studying binary star systems, one stood out. New data prompted us to reanalyze it."

Their findings revealed that CN Lyn’s third star is nearly 10 times more metal-poor than the others, contradicting established theories. "This extreme difference suggests CN Lyn formed in an unexpected way," Bilir said.

He added: "We discovered that two larger stars captured a smaller one in a low-interaction region of the galaxy, proving that we live in a dynamic, not static, universe."

Bilir emphasized: "This discovery was introduced to scientific literature for the first time by Turkish astrophysicists, reshaping our understanding of star formation."

'This star formed while our galaxy was still taking shape.'

Bilir pointed out a significant finding: "Our calculations show that CN Lyn formed 50,000 light-years from the galactic center, but its third star was later captured in a low-gravity region."

The two main stars are 4 billion years old, while the third star is 12.5 billion years old, making it a halo star. "This star formed while our galaxy was still taking shape," Bilir said.

Professor Volkan Bakis from Akdeniz University analyzed a decade’s worth of data and confirmed the existence of the third celestial body.

He said: "This third star follows a 37 light-minute orbit, affecting the movement of the binary stars and delaying the light we receive."

'This challenges our current understanding of how stars form'

Neslihan Alan, a researcher at Istanbul University, explained that stars typically form in clusters from large molecular clouds.

However, their research showed that this system formed at the galaxy’s edge, with the third component joining later from the halo.

"We used different methods and an interdisciplinary approach to gain more comprehensive insights," Alan said. "This challenges our current understanding of how stars form," she added.

'No other system like this exists in the literature.'

Gokhan Yucel, another researcher at Istanbul University, examined data from both ground- and space-based telescopes. "No other system like this exists in the literature," he said, confirming that the third star is chemically distinct, extremely metal-poor, and one of the oldest stars in the universe.

'The third star's age and composition did not match the others'

Remziye Canbay, also from Istanbul University, studied CN Lyn’s kinematics and orbital dynamics. "The third star's age and composition didn’t match the others," she said.

While the primary stars formed in a metal-poor region, the third star originated during the galaxy’s formation and was later drawn in by gravity, challenging existing theories on the evolution of multi-star systems.