JWST Delivers the Clearest Infrared Portrait of M87’s Jet
The James Webb Space Telescope (JWST) has produced the most detailed infrared image yet of the colossal jet blasting from the heart of the giant elliptical galaxy M87. In four infrared bands captured by JWST’s Near Infrared Camera (NIRCam), the jet appears as a luminous pink ribbon stretching across a hazy violet backdrop, revealing the dynamic and energetic processes that unfold near a supermassive black hole.
So far, M87 has served as a natural laboratory for high-energy physics. Its jet is powered by the galaxy’s central black hole, an object designated M87* that drew worldwide attention in 2019 as the first black hole ever photographed directly. JWST’s new infrared view adds a crucial layer of detail to what we already know from radio and X-ray observations, helping scientists trace how particles are accelerated, cooled, and guided by magnetic fields as they travel away from the black hole.
A Closer Look at the Core: Helical Jets and Distinct Knots
Closer to the galaxy’s core, the jet adopts a helical structure that suggests intertwined magnetic fields shaping the flow of plasma. In JWST’s image, a slower-moving feature labeled knot L is visible, along with a brighter region known as HST-1, famous for its rapid and sometimes seemingly superluminal motion. The new infrared portrait shows HST-1 splitting into two substructures with differing emission properties, a smoking gun for shocks and complex particle dynamics in the vicinity of the black hole. This level of detail helps researchers understand how energy is injected and redistributed as jet material threads through the galactic environment.
The Faint Counter-Jet: A Rare Infrared View
For the first time in infrared light, Webb has captured the faint counter-jet about 6,000 light-years from the black hole. This opposing stream, moving away from us at nearly light speed, is notoriously difficult to detect because its light is Doppler-dimmed. JWST reveals two filaments connected by a hotspot, forming a delicate C-shape that matches what radio observations have long hinted at. Detecting the counter-jet in infrared provides new clues about the symmetry of the outflow and the efficiency of particle acceleration on the opposite side of the black hole.
Synchrotron Radiation: The Signature of Energetic Particles
The team’s analysis confirms that the jet shines primarily through synchrotron radiation—light emitted by charged particles spiraling around magnetic field lines. By comparing subtle color differences across the four infrared bands, researchers traced how particles accelerate, lose energy, and twist along the jet’s length. These color signatures offer a direct probe of the jet’s magnetic structure and the cooling timescales of the most energetic particles, providing constraints on models of jet launching and propagation.
Implications for Black Hole Jet Physics
These infrared observations from JWST complement existing radio and X-ray data, offering a more complete picture of how supermassive black holes power colossal jets. The ability to resolve features like knot L and HST-1 in infrared helps scientists test theories about how shocks form near the black hole, how magnetic fields accelerate particles to near-light speeds, and how energy is transported across thousands of light-years of galactic space. The study, led by Jan Röder of the Institute of Astrophysics of Andalusia (Spain) and published in Astronomy & Astrophysics, underscores JWST’s power to illuminate the physics of extreme environments that can never be studied in the lab.
Why M87 Continues to Amaze
Located about 55 million light-years away, M87 has captivated astronomers for over a century. Its famous jet not only narrates the story of a supermassive black hole’s influence on its host galaxy but also serves as a testbed for the physics of relativistic plasmas and strong magnetic fields. Webb’s infrared portrait adds a new dimension to this ongoing investigation, revealing structures and dynamics that were previously elusive in this part of the spectrum.
What Comes Next
With JWST delivering this unprecedented infrared view, researchers are eager to compare these findings with complementary data from ground-based observatories and radio telescopes. By combining multi-wavelength observations, scientists can refine models of jet formation, track particle acceleration in real time, and deepen our understanding of how supermassive black holes shape galaxies across the cosmos.
