In 1781, when French astronomer Charles Messier added Messier 87 to his now-famous list of astronomical objects, the Messier catalogue, he saw the galaxy as just a fuzzy point of light in the night sky. But today we know M87 is a supergiant elliptical galaxy, home to a supermassive black hole that recently made history as the first to ever be imaged.
M87, which has some 50 satellite galaxies swirling around it, is located around 53 million light years from us. The galaxy measures 240,000 light years across, and is estimated to be about 200 times as massive as the Milky Way. Its black hole M87* alone weighs in at around 6.5 billion solar masses, and spews beams of matter and radiation traveling at nearly the speed of light, called relativistic jets, that can be seen from Earth.
Black holes are still-mysterious objects with a gravitational pull so intense, not even light can escape. That’s made black holes difficult to study. But scientists with the Event Horizon Telescope, a network of radio observatories around the world, overcame that limitation, releasing a picture of M87* and its bright accretion disk in 2019, the first-ever image of a black hole.
If you’re searching for M87 in the night sky, you may also get a glimpse of the relativistic jets that shoot out from the central black hole. Measuring thousands of light years in length, the jets appear to move faster than the speed of light because of the way they are oriented towards us. Because jets like these only form on massive black holes that are actively feeding on matter, they are relatively rare in the observable universe.