Some fragments of the jet from supermassive black hole M87* streak at a speed five times higher than that of light... in appearance.
The jets of M87* are powerful flows of matter that escape from the poles of the black hole at a speed close to that of light. Fueled by the fall of gas and dust, they extend over thousands of light-years. These structures play a key role in how supermassive black holes redistribute energy in their host galaxy.
Credit: X-ray: NASA/CXC/Univ. Laval/C. Poitras et al.; IR: NASA/CSA/STScI; Radio:NSF/NRAO/VLA; Optical: NASA/ESA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare
Astronomers have obtained, thanks to Chandra, the sharpest image ever captured of this jet in X-rays. Their data, spread over more than ten years, highlight dynamic transformations where blurred shapes previously reigned. Structures that were once indistinct now become distinct, paving the way for tracking the evolution of the jet over time.
The apparent superluminal motion of certain parts of the jet is not a violation of the laws of physics. According to the theory of special relativity, nothing can travel faster than light. This optical phenomenon occurs when matter moves almost at the speed of light directly towards Earth, creating an impression of greater speed.
These observations from Chandra mark a notable advance in understanding how particles are accelerated to such high energies in jets. They also help to better grasp how the energy released near the black hole is transported by the jet and transferred into the host galaxy, influencing its evolution.
M87*, located 55 million light-years away, became famous in 2019 as the first black hole whose image was captured. The new X-ray data complement this image by offering an unprecedented perspective of the dynamic activity of its jet, opening the door to future studies on these objects of rare intensity.