Event Horizon Telescope advances imaging of black holes and jets

Event Horizon Telescope advances imaging of black holes and jets
by Clarence Oxford
Los Angeles CA (SPX) Dec 18, 2024

The Event Horizon Telescope (EHT), renowned for its first images of black holes, is advancing its mission by exploring how black holes create powerful jets. A research team led by Anne-Kathrin Baczko from Chalmers University of Technology, Sweden, has demonstrated that the EHT can capture detailed images of a supermassive black hole and its jets in galaxy NGC 1052, 60 million light-years away. This effort also confirmed the presence of strong magnetic fields near the black hole's edge.

A major question for astronomers is how supermassive black holes launch jets of high-energy particles at nearly the speed of light. The team has moved closer to answering this by analyzing the central region of NGC 1052 using coordinated measurements from interconnected radio telescopes. These findings are detailed in a paper published in Astronomy and Astrophysics on December 17, 2024.

Anne-Kathrin Baczko, the project's leader and astronomer at Onsala Space Observatory, Chalmers University of Technology, explained the challenge of imaging NGC 1052. "The center of this galaxy is a promising target for imaging with the Event Horizon Telescope, but it's faint, complex, and more challenging than all other sources we've attempted so far," she said.

The black hole in NGC 1052 generates twin jets that extend thousands of light-years. "We want to investigate not just the black hole itself, but also the origins of the jets which stream out from the east and west sides of the black hole as seen from Earth," added Eduardo Ros, an astronomer at the Max Planck Institute for Radio Astronomy in Bonn, Germany.

Achieving New Insights with Advanced Techniques

The team conducted observations using five EHT telescopes, including ALMA in Chile, and additional telescopes to ensure optimal data collection. "For such a faint and unknown target, we were not sure if we would get any data at all. But the strategy worked, thanks in particular to the sensitivity of ALMA and complementary data from many other telescopes," Baczko noted.

The research confirmed that imaging the black hole and its jets is feasible. Two key factors made this possible: the bright radio emissions around the black hole at a detectable frequency and the similarity in size of the jet formation region to the ring of M87.

The team also estimated the magnetic field strength near the black hole's event horizon at 2.6 tesla, about 40,000 times stronger than Earth's magnetic field. Matthias Kadler, an astronomer at the University of Wurzburg in Germany, stated, "This is such a powerful magnetic field that we think it can probably stop material from falling into the black hole. That in turn can help to launch the galaxy's two jets."

The research paves the way for future studies with advanced telescope networks like the next-generation Very Large Array (ngVLA) and the next-generation Event Horizon Telescope (ngEHT). "Our measurements give us a clearer idea of how the innermost center of the galaxy shines at different wavelengths. Its spectrum is bright at wavelengths around one millimeter, where we can make the very sharpest images today. It's even brighter at slightly longer wavelengths, which makes it a prime target for the next generation of radio telescopes," Kadler concluded.

Research Report:The putative center in NGC 1052