Which satellite played a key role in confirming the presence of the smaller black hole orbiting a larger black hole in the galaxy OJ 287, as observed in the international study?

The international study involving 32 scientists from 10 countries marked the first direct observation of a smaller black hole orbiting a larger one in the galaxy OJ 287. This groundbreaking observation was confirmed by NASA's Transiting Exoplanet Survey Satellite (TESS) and other telescopes, including NASA's Swift. TESS, which typically searches for exoplanets, detected a 12-hour burst of light on November 12, 2021, confirming the presence of the smaller black hole. This burst of brightness occurs when the smaller black hole consumes part of the accretion disk of the larger black hole, causing a temporary "yellow" jet of gas. The discovery is significant for the future detection of nano-Hertz gravitational waves, as noted by A. Gopakumar from the Tata Institute of Fundamental Research.