The face-on spiral galaxy M61 is one of the largest members of the Virgo Cluster, an assembly of more than a thousand galaxies at the centre of the even more expansive Virgo Supercluster. Discovered in 1779 by Barnaba Oriani, just six days before Charles Messier realised it wasn’t a comet, M61 is a familiar target for professional and amateur astronomers alike, home to a supermassive black hole at the heart of a dense stellar nucleus. Located 50 million light years from the Milky Way in the constellation Virgo, the galaxy’s spiral arms are populated by billions of stars, the result of rapid star formation. This image was captured by the European Southern Observatory’s Cosmic Gems Programme.
The early universe was a chaotic mess of gas and matter that only began to coalesce into distinct galaxies hundreds of millions of years after the Big Bang. It would take several billion more years for such galaxies to assemble into massive galaxy clusters — or so scientists had thought. Now astronomers have detected a massive, sprawling, churning galaxy cluster that formed only 3.8 billion years after the Big Bang, some 10 billion light years from Earth.
NGC 4639 is a beautiful example of a type of galaxy known as a barred spiral. It lies over 70 million light-years away in the constellation of Virgo and is one of about 1500 galaxies that make up the Virgo Cluster. But NGC 4639 also conceals a dark secret in its core — a massive black hole that is consuming the surrounding gas and known as an active galactic nucleus (AGN).