NASA/ESA's Hubble Space Telescope detected a supermassive black hole approximately 300 million light-years away in the giant elliptical galaxy NGC 4889, which is located in the Coma Cluster, as outlined in a press release. The black hole is approximately 21 billion times the mass of the sun and possesses an event horizon with a diameter of around 130 billion kilometers - about 15 times the diameter of Neptune's orbit from the sun.
Despite its massive size, astronomers believe this supermassive black hole is past the point of feeding and is currently in a state of rest. In fact, the environment within the galaxy is so peaceful that there are stars forming in the remaining gas forms and orbiting around the black hole undisturbed.
However, when it was active, NGC 4889's supermassive black hole was driven by a process known as hot accretion, according to Fox News.
"When galactic material - such as gas, dust and other debris - slowly fell inwards towards the black hole, it accumulated and formed an accretion disc," said the ESA. "Orbiting the black hole, this spinning disc of material was accelerated by the black hole's immense gravitational pull and heated to millions of degrees. This heated material also expelled gigantic and very energetic jets."
Due to the fact that light cannot escape the gravitational pull of a black hole, direct observation is impossible, according to the Daily Mail, which is why scientists used the Keck II Observatory and Gemini North Telescope to measure the velocity of the stars moving around NGC 4889's center, allowing them to reveal the mass of the supermassive black hole.
