![]() ![]() There’s more to figure out about black hole jets and their role in the cosmos. The new image “seems to heavily favor MAD models,” said Alexander Chen, a theoretical astrophysicist at the University of Colorado who is not part of EHT. But the strongly polarized light in the Event Horizon Telescope’s new photo points to strong magnetic fields, and therefore to the MAD version of events. SANE models, which assume weaker fields, were long considered more plausible. These competing ideas paint opposing pictures of a black hole’s milieu and, in particular, the origin and strength of its magnetic field. Moreover, the new observations point to one of two rival versions of the Blandford-Znajek process that have been developed and explored in hundreds of computer simulations in recent decades, known as the MAD and SANE jet-launching scenarios. ![]() “I’m very chuffed,” Znajek, now a retired Cambridge city councilor, said by email. “And the shape of the magnetic field is also spiral … which means it’s able to launch a jet.” “What we see in our image is ordered polarization in a spiral shape,” said Issaoun, who was involved in analyzing the polarization measurements. This, they claimed, is the jet - and a big asterisk on the naive notion that nothing escapes black holes.Īt the time, all ingredients of the process were speculative, but the new observations confirm the Blandford-Znajek idea. Roger Blandford and Roman Znajek, young physicists at the University of Cambridge in 1977, argued that rotating supermassive black holes will twist ambient magnetic fields into a tight helix, and that this twisting will create a voltage that draws energy up and out of the hole and along the helix. Unlike in the first photo, the ring in the new image has stripes, indicating that the light is strongly polarized.Įxperts say the spiral pattern of the stripes results from a strong, orderly magnetic field around the M87 black hole, and that this represents the first significant empirical evidence in favor of a popular 44-year-old theory of jet launching, known as the Blandford-Znajek process. Both images show the glowing plasma around the supermassive black hole at the center of the galaxy M87, whose giant jet rises outside the frame. Several weeks ago, the EHT released its second photo of a black hole - another view of the same fiery ring pitted by darkness seen in 2019. Now, through the work of Issaoun and her colleagues on the black hole-observing Event Horizon Telescope (EHT) team, the mystery has started to unravel. “One of the biggest mysteries in the universe is how black holes launch jets,” said Sara Issaoun, an astrophysicist at Radboud University in the Netherlands. ![]() But why jets shoot out from the edges of many black holes has proved far harder to understand. Physicists know why stuff goes in: Black holes have so much gravity that they trap even light, which cloaks them in spheres of invisibility. They power thin beams of plasma called jets that extend thousands of light-years into space, forming glowing line segments seen all across the cosmos. Paradoxically, black holes, those infamous swallowers of light and matter, also spew light and matter outward with unparalleled might and efficiency. ![]()
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