The jet from the blazar OJ 287, located 4 billion light-years away in the direction of the Cancer constellation, flipped its orientation by more than 300 degrees over a period of one and a half years, Brickininfo TV reported.
The Unprecedented Signal from OJ 287
A blazar is an active galactic nucleus with a jet of charged particles and plasma pointed almost directly at Earth. The scientists tracked changes in the jet's polarization using radio waves. This method allows them to study the magnetic field structure and the surrounding material around the black hole.
The data, collected from 2012 to 2023, came from a global network. This included the Korean VLBI Network (KVN) in South Korea, the Atacama Large Millimeter/submillimeter Array in Chile, and the Metsähovi Radio Observatory in Finland. The observations also included data from visible light wavelengths.
Jet Polarization Twisted by Field
The analysis revealed a dramatic anomaly between 2015 and 2017. During this 1.5-year window, the direction of polarization twisted by over 300 degrees. This is the highest confirmed polarization change ever seen in a supermassive black hole jet. The shift was not isolated; it coincided with a significant increase in radio wave flares from the object.
These flares are thought to occur when particle jets collide with existing material around the black hole. It suggests the radiation-emitting region is moving through a helical, or spiral, magnetic field structure around the supermassive black hole. This data provides crucial evidence for the jet's internal structure, which is difficult to measure directly due to its geometry and the specific viewing angle from Earth.
What This Discovery Means for Black Hole Physics
This finding advances the understanding of black hole jet physics. The helical magnetic field model, suggested by the data, helps explain how these powerful jets are formed and collimated. The new polarization analysis method developed by the team can now be applied to study other supermassive black holes.
This could lead to a better understanding of these cosmic phenomena across the universe. The direct observation of such a large and rapid polarization change confirms theoretical models that predict complex magnetic field configurations in the vicinity of these massive objects. The study, published in The Astrophysical Journal, offers a tangible piece of evidence for processes that were once purely theoretical.
Polarization Reversed in Jet
NARIT researchers found OJ 287’s jet flipped its polarization by over 300 degrees in 1.5 years. This extreme event, tied to increased radio flares, confirms the presence of a spiral magnetic field around the supermassive black hole, providing new insight into how these cosmic jets work.
