Utilizes data from 10m space-based wireless telescopes, including Radioastron. Astronomers have formed a network of 27 ground observation stations focused on OJ 287, a galaxy approximately 5 billion light-years distant from the Cancer constellations.
This image of OJ 287 reveals the sharply curved ribbon-like structure of the plasma jet emitted from its center. Image credits: Efthalia Traianou / Heidelberg University / IWR.
“Among the different types of active galactic nuclei, BL Lacertae (BL LAC) objects are notable for their rapid, large-amplitude variability and significant polarization across multiple wavelengths due to relativistic jets aligned closely with our line of sight.”
“A standout example of this subclass is OJ 287, characterized by a redshift of z = 0.306.”
Optical observations of OJ 287 have yielded an extensive light curve extending back to the 1880s, covering nearly 150 years.
This comprehensive dataset has uncovered periodic brightness variations, featuring marked 60-year cycles and notable high-brightness flares with recurrent double peaks occurring approximately every 12 years.
These periodic changes can be attributed to the presence of a binary supermassive black hole system, where secondary supermassive black holes follow eccentric precession paths around the more massive primary.
“The level of detail in the new images allows us to see the structure of the OJ 287 Galaxy like never before,” stated Dr. Traianou.
“The images penetrate deep into the galaxy’s center, revealing the jet’s sharply curved ribbon-like structure.”
“This also provides new insights into the composition and dynamics of plasma jets.”
“Certain regions exceed temperatures of 10 trillion Kelvin, indicating the release of extreme energy and movement near the black hole.”
Astronomers have also monitored the development, dispersion, and interactions of new shock waves along the jet, linking them to energies in the range of trillions of electron volts from rare gamma-ray observations made in 2017.
Using Radioastron and 27 terrestrial observatories, they captured images of OJ 287 across the radio spectrum.
The imaging relies on measurement techniques that utilize overlapping waves related to the properties of light waves.
“Interference measurement images bolster the hypothesis that a binary supermassive black hole resides within OJ 287,” the researchers commented.
“This also offers critical insights on how these black holes influence the shape and direction of the emitted plasma jet.”
“These unique characteristics position the galaxy as an ideal candidate for further studies on black hole mergers and associated gravitational waves.”
Survey results will be published in the journal Astronomy and Astrophysics.
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E. Traianou et al. 2025. Reveal ribbon-like jets on OJ 287 via Radioastron. A&A 700, A16; doi: 10.1051/0004-6361/202554929
Source: www.sci.news
