A cosmic ribbon of plasma twisting through deep space has been revealed in stunning detail at the center of a distant galaxy, which is thought to harbor a pair of merging black holes.
Using the Spektr-R satellite, a Heidelberg University-led team has captured a stunning image revealing the massive plasma jet at the heart of the enigmatic galaxy OJ 287, offering new insights into how black holes influence their cosmic surroundings.
Astronomers have long been intrigued by OJ 287’s fluctuating brightness, believed to be the result of two supermassive black holes in the process of merging. The new image lends strong support to this theory and provides an unprecedented view of the galaxy’s central jet structure.
OJ 287 and Black Holes
OJ 287 is classified as a blazar—a type of galaxy with a supermassive black hole at its core that emits a jet of radiation pointed directly toward Earth, making it appear especially bright from our vantage point. Even among blazars, OJ 287 stands out for its extraordinary luminosity and frequent outbursts. At its center, one or more black holes consume surrounding matter, producing powerful plasma jets composed of heavy atoms, intense heat, radiation, and magnetic fields.
“We have never before observed a structure in the OJ 287 galaxy at the level of detail seen in the new image,” said lead author Dr Efthalia Traianou, a postdoctoral researcher in the team of Dr Roman Gold at the Interdisciplinary Center for Scientific Computing of Heidelberg University.
A Spectacular Image Reveals a Plasma Ribbon Phenomena
Dr. Traianou’s team successfully imaged deep into the galactic center of OJ 287, identifying a curving, ribbon-like plasma jet within. Thanks to the image’s high resolution, researchers were able to gain a better understanding of the jet’s composition and dynamics. Their calculations revealed localized temperatures exceeding ten trillion degrees Kelvin—evidence of extreme energy events taking place near the black hole.
The team also revisited a puzzling gamma-ray signal recorded in 2017. Upon reanalysis, they discovered a shockwave, measuring roughly a trillion electron volts, propagating and colliding along the jet path.
To obtain the image, the international team used a ground-space radio interferometer, effectively creating a virtual telescope with a diameter five times that of Earth. This system combined one orbital instrument—the 10-meter RadioAstron antenna aboard the Spektr-R satellite—with a network of 27 ground-based observatories. This configuration enabled the team to achieve an extraordinarily high image resolution.
RadioAstron’s data, which contributed to the findings, was collected in April 2016 over a 15-hour observation window. To process the data, scientists employed a technique that involved the overlap of light waves. The Max Planck Institute for Radio Astronomy’s software, DiFX, handled the initial processing, and the team then applied additional analysis tools to generate the final image.
Further Black Hole Research
This study provides a significant starting point for continued investigations into OJ 287. The researchers have produced compelling evidence supporting the long-standing theory of a binary black hole system—one believed to be the central black hole, with a second orbiting on a roughly 60-year cycle. The work also offers deeper insight into how black holes generate and orient plasma jets.
Beyond its unusual brightness and activity, OJ 287 is of further interest to scientists for its potential connection to gravitational wave events, such as those first observed by the LIGO-VIRGO collaboration in 2015.
“Its special properties make the galaxy an ideal candidate for further research into merging black holes and the associated gravitational waves,” Traianou concluded.
The recent paper, “Revealing a Ribbon-like Jet in OJ 287 with RadioAstron,” was published on July 30, 2025, in Astronomy & Astrophysics.
Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.