Estimated reading time: 4-5 minutes
ATLANTA – An international team of astrophysicists has discovered hundreds of mysterious structures in the center of the Milky Way galaxy.
These one-dimensional cosmic filaments are hundreds of horizontal or radial filaments – slender, long bodies of luminous gas that likely originated a few million years ago when the outflow from Sagittarius A*, the Milky Way’s central supermassive black hole, collided with surrounding material, Accordingly. to A study published on Friday In Astrophysical Journal Letters. The threads are relatively short in length, from 5 to 10 each light years.
The findings come nearly 40 years after Farhad Yousefzadeh, lead author of the study, and other researchers I discovered another demographic Approximately 1,000 one-dimensional, vertical and much larger filaments each up to 150 light-years across, near the galactic center. Yousefzadeh and his colleagues also found hundreds of vertical filaments paired and clustered in the same region in 2022, realizing that these filaments were likely associated with Sagittarius A* activity rather than supernova explosions, which they had previously thought. The new study reinforces and builds on previous findings.
It was a surprise, said Yousifzadeh, a professor of physics and astronomy at Northwestern University’s Weinberg College of Arts and Sciences, to find “a new set of structures that seem to point in the direction of the black hole.” press release.
“I was really shocked when I saw these things. We had to do a lot of work to prove that we weren’t fooling ourselves,” added Yousefzadeh, who is also a member of the Center for Interdisciplinary Exploration and Research in Astrophysics. “We found that these filaments are not random but appear to be related to the black hole’s outflow. … It is satisfying when one finds order in the (center) chaotic field of our galaxy’s nucleus.”
The findings regarding the black hole located about 26,000 light-years from Earth are “really exciting” and “show how beautiful the universe is,” said Erica Hamden, an assistant professor of astronomy at the University of Arizona who was not involved in the study. the study.
Sagittarius A* “is the closest supermassive black hole to us, but it’s relatively quiet and therefore difficult to really study,” Hamden added. “But this work provides evidence that it was recently releasing a great deal of energy into space in the form of a jet and conical flow.”
Learn more about the Milky Way
The researchers found the structures by analyzing images produced by the Radio Astronomy Observatory in South Africa Meerkat telescopewhich contains 64 satellite dishes each 65 feet (nearly 20 meters) high and connected across 5 miles (nearly 8 kilometers) of a sparsely populated area with minimal interference.
“Meerkat’s notes have changed the rules of the game,” Yousefzadeh said. “It really is a technical feat of radio astronomers.”
Despite the similarities between the newly discovered hyphae and those identified in 1984, the authors of the new study don’t think the populations share exactly the same traits.
The vertical filaments lie perpendicular to the galactic plane, while the horizontal filaments are parallel to the plane and point radially toward the black hole, according to the news release. Vertical filaments surround the core of the Milky Way, but horizontal filaments appear to propagate to one side, toward the black hole.
“The distribution and alignment of the filaments can help show how materials moved and deformed in the past,” Hamden said.
Their behavior is also different: the horizontal filaments emit thermal radiation and the substances associated with it molecular clouds The authors write that an integral part or all of the outflow from the black hole. molecular clouds It consists of gas, dust and stars. On the other hand, vertical threads are magnetic and riveted cosmic ray electrons It moves at nearly the speed of light.
The authors believe that further study of the newly discovered filaments could help them “learn more about the direction of rotation and accretion of the black disk,” Yousefzadeh said.
Black hole accumulation disc It is the thin, hot structure produced by material from a nearby star being pulled into a circle around a black hole.
Follow-up is also needed, Hamden said, to determine whether outflow from the black hole, and thus more filaments, appears on either side of the black hole. A jet in this context is a packet of matter ejected from some astronomical body.
Hamden added that the black hole “ejectes jets symmetrically … so there must be a pair”. “One way to confirm that the (filamentous) structure was created by something like jetting is to find both sides of it.”
This, she said, would add “to the complex and powerful picture of our Milky Way”.
Yousefzadeh said he believed their work was “never complete”.
“We always need to make new observations, continue to challenge our ideas and sharpen our analysis,” he said.