Most quasars They require very sophisticated instruments to observe. However, some, not too many, are so bright that they can even be seen amateur astronomer with his private telescope. This is, for example, the case Coolant 287, a quasar that just made the news for capturing the first image of two black holes orbiting each other.
The discovery has just been published in Astrophysical Journalled by an international team of scientists, with Mauri Valtonenfrom the University of Turku (Finland), at the helm. These scientists, like many others, were very attracted to the brightness of OJ 287. The brightness of a quasar is usually due tohordes of radiation emitted by a black hole. In this case, to create such brightness, it would have to be a colossal black hole. But what if they were two black holes?
A series of fluctuations observed in quasar brightness in recent years has led to the belief that there may be two such black objects. feed him. To verify this, Valtonen and his team took pictures from a satellite that was near the Moon at the time. Until now, measurements have only been carried out using ground-based telescopes. They were not powerful enough, so there was a lot of uncertainty around OJ 287.
The decision to use a much closer satellite was critical. And indeed, they discovered that there is not one, but two black holes orbiting each other. Plus, if that wasn’t interesting enough, they managed to immortalize the scene. At least when it comes to photographing black holes.
These are the basic concepts you should know
Before talking about what these scientists observed in a quasar, we must remember what a quasar is. Generally speaking, this is a celestial body located in center of galaxieswhich shows great brightness. This brightness always comes from black hole activity.
Let’s then remember what a black hole is. It’s about space-time regions with such a concentration of mass that its gravitational pull does not allow anything to escape. Anything that goes beyond the limit zone known as event horizon will be swallowed up by a black hole. Turning on the light. This is why they are radically dark and impossible to photograph. But they emit radiation.
In 1974, Stephen Hawking calculated that, due to certain quantum effects, black holes should also emit particles. This would mean that not only would they not grow larger and larger, but they would shrink very little by little until they reached the minimum mass at which the black hole would collapse and die after the big bang. The sum of these particles emitted from the black hole is called Hawking radiation. And the best part is that this radiation can be detected. No matter how dark a black hole is, we can determine where it is.
In addition, the black hole revolves around throttle disc and povo trying to avoid his attraction. This is known as accretion disk and can also be detected.
Both questions are important because, on the one hand, the radiation helps illuminate the quasar, which has a black hole at its center, and on the other, the accretion disk is what allows black holes to be photographed. The black hole is not captured because it is completely dark, but silhouette depicting an accretion disk.
How was the image of two black holes obtained?
With all this clear, we can better understand what happened to the quasar OJ 287. There is usually a supermassive black hole, with a mass equivalent to the mass of the Sun several million times. Given its great brightness, it was expected to be gigantic. However, recently 136 years of observations Fluctuations in the quasar’s brightness are observed every 12 years. This led astronomers to speculate that an object might exist here. interrupting the brightness that reaches us from the black hole at the center of the quasar. In fact, what if it was just another black hole?
There was no way to know this from observations made from Earth. So these scientists turned to the satellite RadioAstronequipped with an instrument that performs the functions of a radio telescope. Light in the form of radio waves coming from black holes is captured by this type of telescope. Having one working in space was vital to being able to capture the silhouette of not one, but two black holes.
The image of two black holes is a first in history. This not only confirms the hypothesis of this binary system, but also demonstrates how far new technologies in astronomy. You’ll also be able to learn much more about the two black holes involved. For example, we now know that the largest of them has colossal in size, 18 billion times the mass of the Sun, while the other, with 150 million solar massesmuch smaller, but still huge.
The mystery of the brightness of the quasar OJ 287 is revealed in an image that has gone down in scientific history. What’s next?
Source: Hiper Textual
