Scientists have confirmed that the supermassive black hole M87*, known for its iconic image of a fuzzy orange donut, is indeed spinning. M87* resides in the heart of the Messier 87 (M87) galaxy, located about 55 million light-years away from Earth. The announcement came after two decades of observation using a network of radio telescopes.
The researchers were particularly interested in studying the powerful jet of radiation and particles emanating from M87*. They discovered that this jet follows an 11-year cycle, swinging like a pendulum. This phenomenon is believed to be the result of gravitational interactions between the black hole, which is estimated to be 6.5 billion times more massive than the sun, and the surrounding material disk. The findings provide solid evidence of the black hole’s spin.
To confirm the swing period of the jets, the team collected high-resolution data over two decades and conducted a thorough analysis. They determined that the jet changes its direction by approximately 10 degrees every 11 years. These results align with supercomputer simulations and contribute to our understanding of how black holes form and evolve.
The study also supports Albert Einstein’s theory of general relativity, which suggests that a spinning black hole pulls in the surrounding fabric of space and time. This effect, known as “frame-dragging,” occurs when the black hole’s spin axis is not perfectly aligned with the rotation axis of the surrounding accretion disk.
The researchers compare these observations to wobbling jets seen from another black hole closer to Earth, which oscillates on a much faster timescale of a few minutes. However, the longer swing period observed in M87* aligns with Einstein’s predictions.
The specific processes that cause black holes to spin are not yet fully understood. One theory proposes that smaller black holes form by consuming star matter through an accretion disk, leading to rapid spinning. Over time, these black holes may merge to form supermassive black holes. Confirming the spin rates of black holes of various sizes could help validate this hypothesis.
In conclusion, the confirmation of the spinning black hole M87* provides valuable insights into the behavior and evolution of black holes. This research, published in the journal Nature, marks a significant step towards understanding these celestial phenomena.
1. The article: “Confirmation: Black Hole M87* is Spinning”
2. Original source: Nature (https://www.nature.com/articles/s41567-021-01354-0)