Pocock, who has worked on the JWST, catalogues the science behind its most stunning images in her new book, Webb's Universe. Here's her pick of the telescope’s best shots

At the heart of our Milky Way galaxy lurks a supermassive black hole about four million times the mass of the sun, called Sagittarius A*. In fact, these objects, which increase in mass over time by eating material that wanders too close,