Washington. The Event Horizon Telescope (EHT) has recorded for the first time in the universe a violent and complex ‘dance’ taking place between two supermassive black holes. According to astronomers, this amazing astronomical event is happening in the center of a quasar named OJ287, located about 1.6 billion light years away from Earth.
This discovery has not only created a stir in the world of astronomy, but has also challenged our understanding of black holes so far. According to scientists, two extremely huge black holes are revolving around each other in the center of OJ287 quasar. During this dangerous gravitational game, extremely powerful rays of energy, called jets, are bursting outwards from them. An unusual curved structure within these jets has been observed in photographs and data recorded by the EHT. These rays of energy did not go on any straight path but appeared to be twisted like a spiral or a coil, which scientists had never been able to see with such clarity till now. The biggest achievement of this research is the confirmation of the ‘helical’ i.e. spiral magnetic field within the black hole jet.
Scientists found that waves of energy within the jets were moving at different speeds. When these waves collide with a powerful magnetic field, instability is created between them. This process is called the ‘Kelvin-Helmholtz instability’ in physics, which works in the same way as a strong wind creates waves on the surface of water. For this reason, the energy and light emanating from the black hole appear bent and rotating. The unprecedented capabilities of the Event Horizon Telescope made this discovery possible. According to scientists, EHT can see so closely that it is as if it can recognize a tennis ball placed on the Moon. Two images taken just five days apart in April 2017 recorded major changes in the jet’s structure and polarization. Capturing these changes in the behavior of the black hole in such a short period is considered a historic achievement in itself.
This discovery also raises questions on old theories. Till now it was believed that the rotation of black hole jets is due to the ‘precession model’ i.e. their wobble. But new observations indicate that this rotation is the result of complex physical processes and magnetic forces operating within the black hole. The energy of the particles within the jet was found to be much more powerful than the magnetic force that gives rise to such instability. Scientists believe that this discovery will give a new direction in the future to understand the structure of black holes, their evolution and their impact on the universe.