Astronomers leveraged data from the Radio Astron satellite to generate radio images of two supermassive black holes located at the core of a distant quasar, OJ287. The secondary black hole follows a 12-year orbit around the primary black hole.
The RadioAstron will map two supermassive black holes at the center of galaxy OJ 287, located about 5 billion light-years away in the constellation Cancer. The middle component corresponds to a primary black hole, while the next higher component indicates a secondary black hole, and the highest component represents the knot of its jet. The apparent elongation of the individual components is not real but rather reflects the beam’s shape. Image credit: Valtonen et al., doi: 10.3847/1538-4357/ae057e.
Quasars are exceptionally luminous galactic nuclei whose brightness arises when a supermassive black hole at the galaxy’s center consumes surrounding cosmic gas and dust.
Previously, astronomers have successfully captured images of a black hole at the center of the Milky Way and another in the nearby galaxy known as Messier 87.
“Quasar OJ 287 is so luminous that even amateur astronomers using commercial telescopes can observe it,” remarked Dr. Mauri Valtonen, an astronomer from the University of Turku.
“What sets OJ 287 apart is that it is believed to have two black holes that orbit each other every 12 years, creating a distinct pattern of light fluctuations over the same interval.”
“The earliest observations of OJ 287 date back to the 19th century, captured through old photographs.”
“At that time, the concept of black holes, not to mention quasars, was unimaginable.”
“OJ 287 was inadvertently captured in photographs while astronomers were focused on other celestial objects.”
In 1982, Dr. Valtonen observed that the brightness of the object varied regularly over a 12-year cycle.
He continued his research as a university scholar and proposed that these brightness variations could be due to two black holes orbiting one another.
Numerous astronomers have been closely monitoring quasars to validate this theory and to gain a comprehensive understanding of the orbital motion of the black holes.
The mystery regarding this orbit was finally clarified four years ago by astronomer Lankeswar Dey from the University of Turku.
The only remaining question was whether both black holes could be detected simultaneously.
The solution came from NASA’s TESS satellite, which identified light emission from both black holes.
However, the images captured under normal light lacked the resolution to distinguish the black holes as separate entities, so they were still represented merely as single points.
What was necessary were images with a resolution 100,000 times greater than that attainable by standard radio telescopes.
In this research, Valtonen and his collaborators compared initial theoretical models with radio images.
The two black holes were precisely positioned in the images where they were anticipated to be.
This finding successfully addressed a question that had lingered for four decades: the existence of black hole pairs.
“For the first time, we were able to create images revealing two black holes in orbit around each other,” noted Dr. Valtonen.
“In the image, the black hole is marked by the powerful jets of particles it emits.”
“While the black hole itself is entirely black, it can be identified by the jets of particles and the luminous gas surrounding it.”
Researchers also discovered a completely new type of jet emanating from black holes.
The jet from the secondary black hole of OJ 287 is twisted, resembling the jet from a spinning garden hose.
“This is due to the smaller black hole moving more swiftly around the primary black hole, causing its jet to be deflected according to its current trajectory,” the authors explained.
Their paper was published in the Astrophysical Journal.
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Mauri J. Valtonen et al. 2025. Secondary jet identified in RadioAstron images of OJ 287. APJ 992, 110; doi: 10.3847/1538-4357/ae057e
Source: www.sci.news
