NASA exoplanet-hunting spacecraft hears a red giant star 'singing' to its partner black hole

Using NASA's Transiting Exoplanet Survey Satellite (TESS), astronomers have listened to the cosmic song a red giant star croons to its black hole companion. The song, related to the starquake studied by TESS, revealed the turbulent history of this red giant, hinting that it once collided and merged with another star.

The rapidly spinning red giant star, a phase stellar bodies around the size of the sun enter when they exhaust their fuel for nuclear fusion, dwells in the binary system Gaia BH2. Located around 3,800 light-years away in the constellation Centaurus, this system was discovered by the European Space Agency (ESA) star mapping spacecraft Gaia in 2023.

The team of astronomers used TESS to observe starquakes rippling through the red giant of Gaia BH2. Just as seismic waves can be