The Event Horizon Telescope is a virtual astronomical instrument that allows multiple observatories at different ends of the world to operate as one. It has been used before to observe black holes, but now they want to look more closely at the jets that quasars throw out.
Task for the Event Horizon Telescope
Astronomers studying the elusive supermassive black holes at the hearts of galaxies are intrigued not only by the cosmic giants themselves, but also by the colossal jets they launch into space at speeds close to the speed of light, the largest of which are known to span millions of light years. In particular, the physics of what creates and accelerates these jets to near-light speeds remains unclear.
A large group of astronomers led by Anne-Kathrin Baczko of Chalmers University of Technology in Sweden are now confident that the Event Horizon Telescope (EHT), a planet-sized array of eight ground-based radio telescopes created through international cooperation, is up to the task.
Black hole in the galaxy NGC 1052
In 2017, the team used the Event Horizon Telescope for the first time to peer into the dust-shrouded heart of a distant galaxy where black hole jets form and accelerate. Galaxy NGC 1052 is located about 60 million light-years away in the constellation Cetus and contains a supermassive black hole that weighs more than 150 million suns and ejects bipolar jets from its east and west sides when viewed from Earth.
The heart of the galaxy is a promising target for the Event Horizon Telescope, but it is “faint and more complex than all the other sources we have tried to study so far,” Baczko said in a statement. “We weren’t sure if we’d get any data at all, but the strategy worked.”
The team’s observations showed that the region of the black hole NGC 1052 emits bright radio waves at millimeter wavelengths. This region of the electromagnetic spectrum is available to the EHT to produce the clearest possible images, according to a paper the team recently published in the journal Astronomy & Astrophysics.
Imaging of supermassive black holes
However, this region shines even brighter at slightly longer wavelengths, making it a prime target for future radio telescopes, such as the next-generation Very Large Array in New Mexico or an improved version of the Event Horizon Telescope, which astronomers hope will produce not only images but also video of black holes.
Meanwhile, the dusty region around the black hole where the jets are generated has been found to be similar in size to the ring around the supermassive black hole M87*, which gained fame in 2019 when it became the first void imaged by the EHT collaboration as a fuzzy orange donut. This means that this region is large enough to be imaged with the EHT at full capacity, the researchers say.
Previous observations of the black hole NGC 1052 led by Baczko found that the magnetic field around the cosmic abyss is 40,000 times stronger than our planet’s magnetic field. “We think it can probably stop material from falling into the black hole,” study co-author Matthias Kadler of the University of Würzburg in Germany said in a statement. “This could help launch two galactic jets.”
According to www.space.com
