The supermassive black hole (SMBH) located in M87 galaxy has been seen to rotate, making its jet fluctuate up to 10 degrees. These latest results verify one of the most essential attributes of black holes that astronomers have believed in for long yet have not been able to proof experimentally.
M87* is the highly scrutinized supermassive black hole (SMBH) that stands out amongst its counterparts. Although it is not the largest SMBH we have discovered, its immense mass of 6.5 billion solar masses far exceeds that of our own galaxy. Consequently, it becomes the most substantial SMBH within close proximity, making it relatively convenient to conduct research on. Notably, in 2019, telescopes from various locations teamed up to generate an iconic image of its shadow projected onto the accretion disk, fueling its widespread recognition.
A large number of astronomers haveuate prior to the pictures, paid particular attention to M87*. Supporting information obtained by more than 20 radio telescopes all around the world from 2000-2022 indicates an 11- year pattern in the movement of the relativistic jet which M87* is ejecting. Seperate images can not prove this precisely, thus a group headed by Dr Cui Yuzhu of Zhejiang Lab gathered 164 photos in two-year allotments. These allotments furthermore balanced out variances which were caused by flare-ups in the jet spanning less than a year.
This kind of black hole and the resulting jet are too colossal to be impacted by any kind of outside force that we are aware of, Therefore, the jet's movements must be triggered within the black hole.
If the black hole is spinning, this is thought to cause movements of the jet’s base to occur in a regular cycle. That is to say, provided the spin axis of the black hole is not in line with its accretion disk's axes of rotation, precession similar to that prompting the Earth's axis to traverse the sky, leading to a 26,000-year cycle in stars' observed positions and weather changes, can be seen.
One of the fundamental attributes of black holes, alongside mass and electric charge, is believed to be their spin. In accordance with the no-hair theorem, these three characteristics carry all the necessary knowledge about black holes. While there have been recent challenges to this concept, they mainly involve introducing additional factors rather than disregarding the importance of spin. Due to the immense gravitational force exerted by black holes, their rotating motion causes spacetime to distort, resulting in frame-dragging. This phenomenon occurs even in relatively small black holes, but for a colossal supermassive black hole like the one mentioned, the effects of frame-dragging would be colossal.
Cui Yuzhu expressed great enthusiasm regarding this significant finding. The necessity to gather detailed data and meticulously analyze M87's structure for a period of twenty years is crucial due to the relatively small misalignment between the black hole and the disk, as well as the 11-year precession period.
The authors observe that although other SMBHs have been analyzed for similar motions, none have been detected so far. However, they emphasize that if the movements are less pronounced or occur over a longer period, they would be more difficult to identify. Therefore, there is no reason to cast doubt on the ubiquity of spin.