On January 23, 2025, astronomers made a groundbreaking observation of a supermassive black hole in the galaxy 1ES 1927+654, located approximately 270 million light-years from Earth. For the first time, they witnessed the ejection of a plasma jet measuring one light-year in length, traveling at one-third the speed of light.
This structure consists of two jets, each about 0.5 light-years wide. The study detailing this discovery was published in The Astrophysical Journal Letters.
The interest in the supermassive black hole began in 2018 when astronomers noted an increase in brightness in visible, ultraviolet, and X-ray light around it, suggesting the emergence of a relativistic jet. After a period of inactivity, ground-based radio telescopes captured the real-time formation of the jet last year.
The black hole, with a mass 1.4 billion times that of the Sun, is known to produce powerful jets that can extend up to 23 million light-years. These jets are a common phenomenon among supermassive black holes actively consuming surrounding matter. Magnetic fields at the poles accelerate particles, resulting in their ejection into space.
While astronomers have previously observed many relativistic jets, this is the first instance of witnessing one being expelled in real time. Researchers believe that the eruption began earlier but was obscured by hot gas that later dissipated.
This finding could enhance our understanding of how powerful jets from supermassive black holes initially develop.