Astronomers Discover a Star That Shouldn’t Exist Near a Black Hole

Astronomers found signs of a past stellar collision in a red giant orbiting a dormant black hole. Starquakes show the star is younger than it appears and spinning unusually fast, challenging long held ideas about stellar evolution, quiet black holes.

Astronomers have uncovered the surprising life story of a distant red giant star quietly circling a dormant black hole an object that appears to break some of astronomy’s most trusted rules. By listening to subtle vibrations in the star’s light, scientists discovered clues pointing to a violent past that includes a possible stellar collision, rapid spin, and a puzzling age mismatch. The findings were published in Astronomical Journal.

Starquakes Reveal a Hidden Past

Using data from NASA’s Transiting Exoplanet Survey Satellite (TESS), researchers detected tiny oscillations often called “starquakes” rippling through the red giant. These vibrations act like X-rays for stars, allowing astronomers to peer deep into their interiors.

What they found was unexpected. Although the star looks chemically ancient, its internal structure reveals it is only about five billion years old. This contradiction suggests the star didn’t live a quiet, solitary life. Instead, it likely gained extra mass long ago possibly by merging with another star or absorbing material during the formation of its black hole companion in the Gaia BH2 system.

Too Young on the Inside, Too Old on the Outside

Chemically, the star is “alpha-rich,” a trait usually associated with the Milky Way’s oldest stars. Normally, such stars formed early in the galaxy’s history. But the star’s vibrations tell a different story, revealing a much younger core.

This rare combination young on the inside, old on the outside has left astronomers scratching their heads. The most likely explanation is that the star’s evolution was disrupted, giving it the chemical fingerprint of an ancient object while resetting its internal clock through a dramatic interaction.

Spinning Faster Than It Should

Adding to the mystery, ground-based observations show the red giant spins once every 398 days far faster than expected for a star of its type. Such speed is difficult to explain unless the star was “spun up” by tidal forces or a past merger.

The discovery challenges existing models of stellar aging and black hole companions. It also hints that many quiet black holes in our galaxy may be hiding similarly unusual partners, waiting to be uncovered through careful observation rather than dramatic X-ray flares.

As future TESS observations roll in, astronomers hope to confirm whether this strange star is truly the survivor of a long-forgotten cosmic collision and what it can teach us about the secret lives of dormant black holes.