In April 2019, the Event Horizon Telescope (EHT) collaboration made history by releasing the first-ever image of a black hole – an object that, until then, had never been directly observed by humanity.
Now, an international team of astronomers has produced the "most detailed X-ray view ever” of a plasma jet shooting from the same supermassive black hole, M87*.
In a paper published on arXiv, the scientists explain how their findings highlight the unique capabilities of NASA’s Chandra Observatory for charting the evolution of vast cosmic phenomena over long timescales.
Visualising a decade of plasma jet evolution
As a supermassive black hole consumes its surrounding matter, dust and gas form a hot, swirling accretion disk. The immense gravitational force, combined with the rapid rotation of the black hole, twists the surrounding magnetic fields into coils at its poles.
These coils essentially act as particle generators, firing powerful jets that extend thousands of light-years throughout the galaxy.
According to NASA, M87*, which is located some 55 million light-years from Earth, has jets that extend more than 3,000 light-years into space. The highly energetic jets soar into the cosmos at relativistic speeds, meaning they almost reach the speed of light.
Led by Camille Poitras, a PhD student in the Faculty of Science and Engineering at Laval University, the astronomers used advanced X-ray image-processing techniques that let them track the evolution of jet structures with never-before-seen detail.
Their image combines a series of observations from Chandra acquired between 2012 and 2025.
Traditionally, X-ray imaging has been utilised alongside other wavelengths when studying black hole jets. While X-ray imagers are excellent at capturing the hottest, most energetic features of a relativistic jet, they show limitations when it comes to clearly resolving some of their other structures.
Radio telescopes, for example, provide sharper details and reveal the longer, extended parts of the jets shooting into the cosmos.
However, in a statement, the Chandra team explains how they used an image-processing technique known as deconvolution to reveal much finer details in their images.
This added detail made the Chandra observations more closely match those of optical and infrared observations from the Hubble and James Webb Space Telescopes, but with the added energy-capturing detail of Chandra’s X-ray imagers.
By combining Chandra observations captured over a period of over ten years, they were able to track the evolution of M87*’s jets with unprecedented detail.
"We could already see changes in the jet, but never with this level of detail in X-rays," says Poitras. "Structures that previously appeared blended together can now be distinguished, allowing us to better follow the jet's evolution over more than a decade of observations."
Moving at ‘five times the speed of light’
Before capturing their historic 2019 image, the EHT team chose the supermassive black hole M87*, in part, because of the fact it is an active black hole with a bright, highly visible accretion disk with relativistic jets.
By contrast, our galaxy’s black hole, Sagittarius A*, is quiet due to a lack of surrounding gas and dust.
The level of activity in M87* also made it a great candidate for the new Chandra observations. According to the team, the new X-ray view of M87*’s jets reveals a more dynamic flow than previously recognized.
Some structures of the colossal energy jets seem almost static, while others appear to be moving at five times the speed of light due to a phenomenon known as superluminal motion.
Superluminal motion is an optical illusion caused when materials travel close to the speed of light in a direction roughly facing Earth. Ultimately, this allows astronomers to observe a jet evolving at an incredibly fast pace.
"These results demonstrate how uniquely powerful Chandra remains for tracking the evolution of extreme phenomena over long timescales," said Gerrit Schellenberger, an astrophysicist at the Harvard & Smithsonian Center for Astrophysics and co-author of the study. "They help us better understand how energy released near a supermassive black hole is carried through its jet and deposited into the surrounding galaxy."
The unprecedented detail in the newly processed Chandra images could help scientists better understand how particles are accelerated to such extreme energies. So extreme that, from some angles, they can appear to be bending the laws of physics.
The research has been published on the preprint site arXiv.
Source: Chandra X-ray Observatory
Fact-checked by Mike McRae
