M87 galaxy Black Hole It shows an oscillating jet, confirming its spin, as deduced from two decades of research in line with the predictions of Einstein’s theory of general relativity.
The nearby radio galaxy M87, located 55 million light-years from Earth and hosting a black hole 6.5 billion times the mass of the Sun, exhibits an oscillating jet that bounces up and down with an amplitude of about 10 degrees. This confirms the existence of black holes. spin.
The study was led by Chinese researcher Dr. Cui Yuzhu. Nature It was carried out by an international team on September 27 using a worldwide network of radio telescopes.
“This monster black hole is indeed spinning.” — Dr. Kazuhiro Haneda
Through extensive analysis of telescope data from 2000 to 2022, the research team found that the jet base’s precession repeats every 11 years, as predicted by Einstein’s theory of general relativity. The study links jet dynamics to the central supermassive black hole and provides evidence that M87’s black hole is rotating.
supermassive black hole phenomenon
The most destructive objects in our universe, supermassive black holes at the centers of active galaxies, can accumulate vast amounts of matter due to their extraordinary gravity and forces. plasma The outflows, known as jets, approach the speed of light and extend thousands of light years away.
The mechanisms of energy transfer between supermassive black holes, their accretion disks, and relativistic jets have puzzled physicists and astronomers for more than a century. A popular theory suggests that energy can be extracted from a rotating black hole, allowing some of the matter surrounding the supermassive black hole to be ejected with great energy. However, the rotation of a supermassive black hole, an important element in this process and the most fundamental parameter other than the black hole’s mass, had not been directly observed.
Focus on M87
For this study, the researchers focused on M87, where the first astrophysical jet was observed in 1918. Because of their proximity, the jet-forming region near the black hole can be analyzed in detail using very long baseline interferometry (VLBI). As exemplified by recent black hole shadow imaging by the Event Horizon Telescope (EHT). By analyzing her VLBI data from M87 obtained over the past 23 years, the research team detected a periodic precessing jet at its root, providing insight into the state of the black hole at its core. provided.
Black hole dynamics and relativity
At the heart of this discovery is an important question: What force in the universe could change the direction of such a powerful jet? The answer may lie in the behavior of the accretion disk, a configuration associated with a central supermassive black hole.
The falling material orbits around the black hole due to its angular momentum, forming a disk-like structure before gradually spiraling inward and eventually being drawn into the black hole. But if a black hole were to rotate, it would have a significant effect on the spacetime around it, dragging nearby objects along its axis of rotation. This phenomenon is known as “frame dragging” and was predicted by Einstein’s theory of general relativity.
“We are excited about this important discovery.” — Choi Okju
The researchers’ extensive analysis shows that the accretion disk’s axis of rotation is misaligned with the black hole’s axis of rotation, causing the precessing jet. Detecting this precession provides unambiguous evidence that M87’s supermassive black hole is indeed rotating, and increases our understanding of the nature of supermassive black holes.
“We are excited about this important discovery,” said Cui Yuzhu, a postdoctoral fellow at the Zhejiang Research Institute in Hangzhou, and lead and corresponding author of the paper. “The slippage between the black hole and the disk is relatively small, and the precession period is about 11 years, so achieving this result required more than 20 years of accumulation and thorough analysis of high-resolution data tracking M87’s structure. is essential.”
“Since EHT successfully imaged the black hole in this galaxy, whether this black hole is rotating has become a central concern of scientists,” added Dr. Kazuhiro Hada of the National Astronomical Observatory of Japan. Ta. “Now, hope has turned to certainty. This monster black hole is indeed spinning.”
Contribution and future impact
This study utilizes the East Asia VLBI Network (EAVN), the Very Long Baseline Array (VLBA), the KVN and VERA Joint Array (KaVA), and a total of 170 epochs of observations from most of the region from East Asia to Italy. Did. Global (eating) network. In total, more than 20 telescopes around the world contributed to this research.
Chinese radio telescopes also contributed to the project, including China’s Tianma 65-meter radio telescope, which has a huge dish and high sensitivity at millimeter wavelengths. In addition, the 26-meter radio telescope in Xinjiang will improve the angular resolution of EAVN observations. High quality data with both high sensitivity and high angular resolution are essential to achieving this outcome.
“The Shigatse 40-meter radio telescope installed in the building by the Shanghai Observatory will further improve EAVN’s millimeter-scale imaging capabilities. It has the best location conditions. It meets our expectations of promoting submillimeter wave facilities for astronomical observation in the country,” said Professor Shen Zhiqiang, Director of the Shanghai Astronomical Observatory, Chinese Academy of Sciences.
While this research sheds light on the mysterious world of supermassive black holes, it also poses formidable challenges. The structure of the accretion disk and the exact values of the spin of the M87 supermassive black hole are still highly uncertain. The study also predicts that there are more sources with this configuration, and scientists have difficulty discovering them.
Reference: “Precessional jet nozzle connected to M87’s rotating black hole” Yuzhu Cui, Kazuhiro Hada, Kazuhiro Kawashima, Motoki Kino, Weikang Lin, Yosuke Mizuno, Hyunwook Ro, Mareki Honma, Kunwoo Yi, Jintao Yu, Jongho Park, Written by Wu Jiang, Zhiqiang Shen, Evgeniya Kravchenko, Juan-Carlos Algava, Xiaopeng Chen, Ilje Cho, Gabriele Giovannini, Marcello Giroletti, Taehyung Chung, Sen Lu Lu, Kotaro Niinuma, Oh. Jung Hwan, Ken Osuga, Satoko Sawada, Son Bong Won, Hiroyuki Takahashi, Mieko Takamura, Fumie Tasaki, Sasha Trippe, Kiyoaki Wajima, Kazunori Akiyama, Tao An, Keiichi Asada, Salvatore Buttaccio, Byun Doyoung, Ran・Cui, Yoshiaki Hagiwara, Tomoya Hirota, Jeffrey Hodgson, Noriyuki Kawaguchi, Jae-young Kim, Sang-sung Lee, Jae-won Lee, Jeong-ae Lee, Giuseppe Maccaferri, Andrea Mellis, Alexei Melnikov, Carlo Migoni, Oh・Sejin, Koichiro Sugiyama, Xuezhen Wang, Yingkang Zhang, Cheng Cheng, Juyongfan, Donggyu Jung, Hyoryong Kim, Jungsook Kim, Hideyuki Kobayashi, Bin Li, Guanghui Lee, Xiaofei Li, Zhiyong Liu, Qing-hui Liu, Xiang Liu, Chun-sik Oh, Tomoaki Oyama, Deok-gyu Roh, Jinqing Wang, Na Wang, Shiqiang Wang, Bo Xia, Hao Yan, Jae-Hwan Yeom, Yoshinori Yonekura, Jianping Yuan, Hua Zhang, Rongbing Zhao, Weiye Zhong, 2023 September 27th, Nature.
DOI: 10.1038/s41586-023-06479-6