New images obtained using the Event Horizon Telescope (EHT) show us a powerful relativistic jet ejected from the supermassive black hole of the galaxy Centaurus A with a resolution sixteen times sharper than before. This data could help unravel the mystery of how matter behaves around these cosmic ogres.
A little over two years ago, the Event Horizon Telescope collaboration revealed the incredible first-ever image of a black hole's shadow. Initiated by Dr. Shep Doelman, of the Harvard-Smithsonian Center for Astrophysics, this adventure involved simulating a giant telescope, the size of the Earth, combining the sensitivity of eight radio telescopes scattered around the world.
In 2017, while working to photograph this famous black hole, found in the center of the M87 galaxy, the Event Horizon Telescope (EHT) also focused on the Centaurus A galaxy, about 12 million light-years away . Discovered in 1949 , it is one of the brightest and largest objects in the night sky under radio wavelengths.
This work ended up producing a spectacular image allowing us to appreciate the birth of the long radio jets emanating from the galaxy's supermassive black hole.
As a reminder, supermassive black holes "swallow" almost anything that comes a little too close. In some cases, however, matter somehow manages to escape the powerful attraction of these objects, eventually traveling millions of light-years through space. Their mechanism of formation is not yet well understood, but we know that these jets are among the most powerful astrophysical phenomena in the universe .
This image shows us details about about 0.6 light days . In other words, it only covers a small region around the giant black hole of 55 million solar masses .
“This allows us for the first time to see and study an extragalactic radio jet at scales less than the distance traveled by light in a day “said astronomer Michael Janssen of the Max Planck Institute for Radio Astronomy in Germany, which publishes the work in the journal Nature Astronomy. "We see up close how a monstrously gigantic jet launched by a supermassive black hole is being born “.
These new images also revealed that the areas of the jet furthest from the center are brighter than the parts closest to the black hole. This phenomenon is still unexplained by researchers. In the future, they plan to rely on space observatories to image the environment surrounding the Centaurus A black hole at even shorter wavelengths and with even higher resolution.
