Observations by NASA’s TESS spacecraft have revealed an unusual phenomenon: a red giant star has been emitting vibrations that resemble a “song” to its black hole companion. These are not just acoustic vibrations, but also valuable information about the star’s internal structure and past.
The red giant is located in the Gaia BH2 binary system, about 3,800 light-years away. Scientists have found that it is rich in minerals, a trait typical of ancient stars, but TESS observations have shown that it is actually about 5 billion years old, younger than it appears.
Furthermore, the star rotates at an unusual speed of about once every 398 days, which suggests that it may have collided or merged with another star, or may have absorbed mass from a star that later became a black hole.
