Supermassive black holes are believed to sit at the center of every galaxy in the Universe. It’s not clear why they are always in the center, but we are safe in the knowledge that those shocking vortexes of nothingness stay where they are supposed to... until they don’t. A recently discovered black hole seems to have been knocked from its post by another galaxy and is now ripping, unanchored, through its own galaxy. Let’s all just take a moment to appreciate the very obedient black hole at the center of the Milky Way, shall we? Usually, black holes form when a star at least five times bigger than the Sun runs out of fuel and falls in on itself to create a damaging void that not even light can escape. There are also massive black holes, sometimes referred to as intermediary-mass black holes, which are 100 to 100,000 times bigger than our Sun.
Chandra X-ray Observatory
Supermassive black holes, instead, contain hundreds of millions of times the mass of our Sun. The largest ones can contain mass as 10 billion Suns. Enormous and supermassive black holes are thought to be at the center of every galaxy in the Universe. This looming existence is basic for the presence of a galaxy, they even grow in tandem with each other, but no one’s totally sure why these black holes always stay at the center.
One supposition is that the black hole existed first, and succeeded to pull an entire galaxy full of things or stuff in around it. Another hypothesis is that the ‘dark matter halo’ that surrounds every galaxy focuses new galaxy material in such a manner that you end up with a massive or supermassive black hole in the center, and stars all over. Regardless of how they got there, supermassive black holes tend to remain in the center of a galaxy, but scientists have hypothesized that on very unusual occasions, something disastrous can knock them free. Now it looks like we have discovered one such 'wandering' supermassive black hole, tearing through the boundaries of galaxy SDSS J141711.07+522540.8, some 4.5 billion light-years from Earth.
We have identified this massive object, called XJ1417+52, for over a decade now, and earlier estimates have placed its mass at around 100,000 times larger than our Sun, and its area at about 3.13 million light years. But back after we first spotted it, it appeared to be fixed to its gigantic center.
The group that discovered it, led by physicist Dacheng Lin from the University of New Hampshire, advises that the black hole broke free when its galaxy merged or crashed with a neighboring galaxy, something that’s likely to happen to the Milky Way in 5 billion years or so.
It’s believed that when this collision occurred, a sun from one galaxy wandered too close to the supermassive black hole of the other one, and the supermassive black hole got dislodged, and the sun shredded. That explains why when the team detected the black hole for the first time between 2000 and 2002, it looked so amazingly bright. Only in the past few years did they succeeded to find the source of this flash. As George Dvorsky explains for Gizmodo, the gaseous debris created by this collision produced a tremendous amount of X-rays that have since been detected by NASA’s Chandra X-ray Observatory and the ESA’s XMM-Newton X-ray observatory.
To give you a hint of how bright the collision was, it was 10 times brighter than the brightest X-ray source ever detected for a possible wandering black hole, and it is also about 10 times more away from us than the earlier record holder. So... should we be concerned about a rogue black hole that's doing what it wants, where it wants? Well, if we somehow work out how to travel to places billions of light years far, the answer is simply no. But spare a thought for whatsoever matter it wanders into in its own galaxy, as death by a black hole is no fun for anyone.