Star passing Milky Way's supermassive black hole. Illustration of the star S2 passing very close to the supermassive black hole at the centre of the Milky Way. As it gets close to the black hole the very strong gravitational field causes the colour of the star to shift slightly to the red, an effect of Einstein's Theory of General Relativity. The colours and sizes of the objects shown here have been exaggerated for clarity. Analysis of data from ESO's Very Large Telescope and other telescopes suggests that the orbit of the star S2 is deviating slightly from the path calculated using classical physics. The deviation can be explained by, and provides a proof of, Einstein's Theory of General Relativity. Image published in 2018.