At https://phys.org/print435378398.html … the odd behaviour of a star led to a second look – and a third. It was decided something was disturbing its orbit – and the researcher opted for a black hole. Not any old black hole but a lonely black hole. It was hiding behind the star, it is alleged. However, digging deeper we learn that they expected to find black holes in this globular cluster as that is what theory said so. Globular clusters are supposed to breed black holes – yet none have been found in association with them until now (and even then it is guesswork). Once again proof of a black hole is envisaged simply by the behaviour of objects in deep space – in this instance, a star behaving oddly. In other cases black holes are equated with transitory beams of light or jets of high energy.
At https://phys.org/print435391067.html … eBOSS (the extended Baryon Oscillation Spectroscopic Survey (surveying galaxies out there in deep space) is part of the Sloan Digital Sky Survey – looking at, among other things, red shift. It used quasars to measure the difference. The work was published by arXiv under the leadership of Zhao Gongbo of the Chinese Academy of Sciences.