Chandra’s Sharpest X-Ray View Yet Reveals M87’s Jet Moving at ‘Five Times the Speed of Light’
Featured image: Composite X-ray/infrared/radio view of the M87 relativistic jet; credit: X-ray: NASA/CXC/Univ. Laval/C. Poitras et al.; IR: NASA/CSA/STScI; Radio: NSF/NRAO/VLA
Between 2012 and 2025, NASA’s Chandra X-ray Observatory stared at the same target: the jet erupting from the supermassive black hole at the heart of the galaxy M87, 55 million light-years away. Now, by applying advanced image-processing techniques to the entire 13-year dataset, an international team has produced the sharpest X-ray view of that jet ever obtained. What it reveals is a structure far more complex and dynamic than previously understood, with some components appearing to travel at nearly five times the speed of light.
> “We could already see changes in the jet, but never with this level of detail in X-rays,” said Camille Poitras, a PhD student at Laval University who led the study. “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.”
The M87 Jet: A Cosmic Particle Accelerator
The supermassive black hole at the center of M87, famously the first black hole ever directly imaged by the Event Horizon Telescope in 2019, contains roughly 6.5 billion times the mass of the Sun. As matter spirals inward, it forms an accretion disk that rotates at near-light speeds. Some of that energy is redirected and launched from the black hole’s poles as a jet of relativistic plasma extending more than 3,000 light-years into intergalactic space.
Chandra has been monitoring that jet since its launch in 1999, but X-ray telescopes have historically struggled to resolve the jet’s internal structures at the same clarity achieved at radio or optical wavelengths. Radio observations from the Very Large Array, for example, routinely produce sharper images of the jet’s extended lobes. Optical and infrared views from Hubble and Webb reveal the cooler, larger-scale features.
X-rays capture something different: the hottest, most energetic regions where particles are accelerated to extreme energies.
Deconvolution: The Key That Unlocked the Detail
The breakthrough came from a technique called deconvolution. By mathematically reversing the blurring effect inherent in X-ray optics, Poitras and her team extracted details from the Chandra data that were previously hidden. The resulting images align much more closely with Hubble and Webb observations, but with the added energy information that only X-rays can provide.
The team, which included researchers from the Harvard & Smithsonian Center for Astrophysics, the International Center for Radio Astronomy Research, and the University of Maryland Baltimore County, presented their findings at the 248th meeting of the American Astronomical Society in Pasadena in June 2026. Their paper, “Resolving the Temporal Evolution of the M87 Jet with <0.1-arcsec Chandra Observations,” is available on arXiv (2606.13800).
Apparent Superluminal Motion and Shocks
The most striking finding is that different parts of the jet move at dramatically different speeds. While some structures appear nearly stationary, others race outward at speeds that, from Earth’s perspective, seem to exceed the speed of light by a factor of five. This phenomenon, known as superluminal motion, is a well-understood optical illusion: when material traveling near the speed of light is aimed roughly toward Earth, the pursuit effect compresses the apparent travel time, making the object appear to move faster than light.
What the illusion reveals is real physics. The observed motions are consistent with computer simulations of shocks produced when different parts of the flowing jet collide, similar to sonic booms in the atmosphere. Magnetic fields threading the jet play a critical role in shaping its structure and confining the plasma.
Chandra’s Enduring Power
For a telescope that launched more than a quarter-century ago, the results demonstrate that Chandra remains an extraordinary instrument for tracking extreme phenomena over long timescales.
> “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 CfA 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 study also carries implications beyond M87. Relativistic jets are a universal feature of active supermassive black holes, and understanding how they accelerate particles, transport energy, and shape their host galaxies is one of the central questions in extragalactic astrophysics. By combining Chandra’s long baseline with new processing techniques, Poitras and her team have demonstrated that M87’s jet is still revealing surprises more than a decade after the observations began.