A rapidly rotating super massive black hole has been found in the heart of a spiral galaxy by ESA’s XMM-Newton and NASA’s NuSTAR space observatories, opening a new window into how galaxies grow. Super massive black holes are thought to lurk in the center of almost all large galaxies, and scientists believe that the evolution of a galaxy is inextricably linked with the evolution of its black hole. How fast a black hole spins is thought to reflect the history of its formation. In this picture, a black hole that grows steadily, fed by a uniform flow of matter spiraling in, should end up spinning rapidly. Rapid rotation could also be the result of two smaller black holes merging. On the other hand, a black hole buffeted by small clumps of material hitting from all directions will end up rotating relatively slowly. These scenarios mirror the formation of the galaxy itself, since a fraction of all the matter drawn into the galaxy finds its way into the black hole. Because of this, astronomers are keen to measure the spin rates of black holes in the hearts of galaxies. One way of doing so is to observe X-rays emitted just outside the ‘event horizon’, the boundary surrounding a black hole beyond which nothing, including light, can escape.
The main point of scientific interest is the mechanics of making the black hole to spin as the can reveal the secrets of the galaxy’s history:
Space Agency’s XMM-Newton X-ray satellites — have calculated the spin rate of this particular black hole, which is dragging all those stars and other nebula fragments into it, like water swirling into a shower drain. ”This is the first time anyone has accurately measured the spin of a supermassive black hole,” said lead author Guido Risaliti. “The black hole’s spin is a memory, a record, of the past history of the galaxy as a whole.” So how fast are we talking? According to the team’s calculations, the outer edges of NGC 1365 are being whipped around at about 84 percent of the speed of light. Most galaxies spin at a much slower rate than that. In other words, enormous stuff like stars and gas giants are traveling millions of miles against their will — in the blink of an eye. A cosmic spin cycle, if you will. How did NGC 1365′s black hole start spinning so fast to begin with? The principle at work here is called the conservation of angular momentum. It’s why a figure skater can spin in place faster when he pulls his arms closer to his body, and why a little girl can get really high on a playground swing if she tucks her legs in at the right time.
Another important thing is discoveries directly related to supernova explosions:
Black holes are created when a supernova explosion destroys a massive star. Scientists have discovered dozens of black holes, but all of them are already formed. So, when scientists recently saw different distorted remains of a supernova, they knew it something special. What the scientists believe they observed was the infant phases of a black hole, or the youngest black hole ever recorded in the Milky Way galaxy. Caught on film by NASA’s Chandra X-ray Observatory, the “remnant,” or W49B, is seen as a vibrant swirl of blues, greens, yellows, and pinks. As seen from Earth, it is about 1,000-years-old and is located roughly 26,000 light years away. A typical black hole, like SS433, is thought to be between 17,000- and 21,000-years-old, as seen from Earth. ”W49B is the first of its kind to be discovered in the galaxy,” Laura Lopez, who led a study on the remnant at the Massachusetts Institute of Technology, said in a statement. “It appears its parent star ended its life in a way that most others don’t.”
Finally, by discovering the secrets of space we can understand the dynamics of its creation and also find possible solution for solving global problems in Earth. Black hole discoveries is a positive step to this direction.