First direct evidence that a giant black hole is spinning

A recent study led by Dr. CUI Yuzhu confirmed that a supermassive black hole is spinning at the center of the neighboring radio galaxy M87.

The research, published in the journal Nature, was carried out by an international team of scientists using a range of radio telescopes from around the world. M87’s oscillating jet Located 55 million light-years from Earth, M87 is home to a massive black hole with a mass about 6.5 billion times that of the Sun. The galaxy has an oscillating gravitational jet, moving up and down with an amplitude of about 10 degrees. Two decades of data The team meticulously analyzed telescope data spanning from 2000 to 2022, revealing a periodic 11-year cycle in the jet base’s precessional motion. This finding is consistent with predictions made by Einstein’s general theory of relativity, which directly links the dynamic behavior of the jet to the rotation of the central supermassive black hole. Surprising finding Analysis shows that the rotation axis of the accretion disk is not aligned with the black hole’s rotation axis, leading to a precession flow. This precession provides clear evidence that M87’s supermassive black hole is in fact rotating.

“We are very excited about this important discovery,” said CUI Yuzhu, study co-author and postdoctoral researcher at Zhejiang Laboratory. “Since the deviation between the black hole and the disk is relatively small and the precession period is about 11 years, it is desirable to accumulate high-resolution data tracking the structure of M87 for two decades and to analyze it extensively. necessary to achieve this goal.” Dr. Kazuhiro Hada of the National Astronomical Observatory of Japan added: “After the success of imaging black holes in this galaxy using EHT, whether this black hole rotates or not is a top concern. of scientists”. “Today, expectation has become certainty. This giant black hole is actually spinning. Historical Significance M87 is historically significant in the field of astronomy, as it was the site of the first astrophysical observation identified in 1918. Due to its relatively close location to Earth, scientists was able to study the jet formation regions near its black hole in intricate detail. using very long baseline interferometry (VLBI). This technique has proven crucial for obtaining high-resolution data, such as recent images of the shadow of a black hole taken with the Event Horizon Telescope (EHT).

Spinning black holes Supermassive black holes, such as M87, are recognized as disruptive objects, capable of accumulating enormous amounts of matter and generating powerful plasma streams or jets. These rays travel at nearly the speed of light, extending thousands of light years into space. The black hole’s rotation plays an important role in this process, drawing energy from the black hole itself, thereby ejecting surrounding matter with significant energy. Frame dragging This rotation also causes a significant impact on the surrounding space-time, pulling nearby objects along its axis of rotation, a phenomenon known as “frame dragging”. This effect, predicted by Einstein’s theory, contributes to the precession of the jet, providing irrefutable evidence of the black hole’s rotation. Global collaboration More than 20 telescopes around the world were involved in the research, with contributions from China’s Tianma 65-meter and Xinjiang 26-meter radio telescopes, known for their high sensitivity and Angular resolution. Future contributions are expected from the 40-meter Shigatse radio telescope, currently under construction by the Shanghai Observatory, which promises enhanced imaging capabilities due to its location on the Tibetan Plateau, an optimal location for observing submillimeter wave lengths. Future discoveries While providing valuable information, the study also leaves a number of questions unanswered, including uncertainties about the structure of the accretion disk and the exact value of rotation of black hole M87.

Scientists hope to discover more sources with similar configurations, which will provide opportunities to improve our understanding of supermassive black holes. Learn more about black holes Black holes, perhaps the most mysterious entities in our universe, challenge the limits of our understanding of physics and time. Born from the ruins of giant stars, they are shrouded in a veil of mystery and enchantment, forcing scientists to constantly reveal their secrets. Formation and Characteristics Stars with a mass about 20 times that of our Sun undergo significant annihilation, leading to the birth of black holes. When these stars run out of nuclear fuel, they can no longer support the force of gravity pushing them inward, causing them to collapse in a spectacular explosion known as a supernova. What’s left is a core where gravity brings everything together into a single point called the singularity, around which a boundary called the event horizon forms. Once the object passes this threshold, escape becomes impossible, even for light, thus making the black hole invisible against the cosmic background. Types of black holes Scientists classify black holes into three main types: stellar, supermassive, and intermediate. Stellar black holes result from the gravitational collapse of massive stars and are typically 20 times the mass of the Sun. Supermassive black holes, hidden at the centers of galaxies, including our own Milky Way, have masses equivalent to millions or billions of suns.

The existence of intermediate black holes, whose masses lie between stellar and supermassive black holes, remains a subject of ongoing research and discussion. Accretion disks and hawk radiation Black holes suck nearby matter into a swirling accretion disk, where intense gravity heats the material, causing it to emit X-rays and other forms of radiation. This broadcast allows scientists to indirectly observe and study black holes. The concept of Hawking radiation proposed by physicist Stephen Hawking shows that black holes can also emit particles due to quantum mechanical effects near the event horizon, leading to a gradual loss of mass and energy.