For the first time, astronomers have seen a jet burst from the center of a distant galaxy that changed direction.
About 1% of supermassives black hole, which are at the center of most galaxies, are surrounded by disks of gas and dust. Debris from this disk that moves toward the growing black hole blasts powerful jets at the speed of light in random directions. These jets push a large amount of energy into the surrounding area and help shape it galaxy Over the ages, therefore, one of the ways astronomers have classified galaxies is by how such jets are oriented.
For example, when the galactic core contains jets of charged particles that are sputtered perpendicularly as seen the worldThey are called Quasar. Sometimes, the jets are aimed directly at Earth and are called galactic cores Blazer. While astronomers know that quasars and blazars exist, the latest discovery is the first time they’ve seen a galaxy in the former group transform into the latter.
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The discovery comes from a distant galaxy called PBC J2333.9-2343, whose center has had jet blasts in the past but has long been quiescent. In the latest study, the astronomers found that the core brought the jets back to life, one of which changed direction “drastically”. Galaxy, which spans four million light years And it is located about 656 million light-years from Earth, shines brightly at radio wavelengths and is thus called a radio galaxy. Given the sharp change in the orientation of the jet, astronomers have redefined giant radio galaxies with a Blazer at its center.
“We started studying this galaxy because it showed strange properties,” said Lorena Hernández-Garcia, an astronomer at the Millennium Institute of Astrophysics in Chile and lead author of the study. statement (opens in new tab). “Our assumption was that the jet changed its direction relative to its supermassive black hole, and we had to do a lot of observations to confirm that idea.”
So Hernandez-Garcia’s team studied galaxies throughout Electromagnetic spectrum — including radio, optical, infrared, X-ray, and ultraviolet wavelengths, and found that one of the jets that had been perpendicular to our line of sight had changed direction by 90 degrees so it now faced Earth. This is “a very exceptional event of jet reorientation” and is necessary to redefine the galaxy, the astronomers said.
Although galaxies are classified based on the orientation of the jets, why they change direction is not well understood. Some astronomers hypothesize that merging galaxies or black holes contribute to occasional bursts of jet activity, and that the directions of the jets change between bursts.
Such activity is not surprising, since astronomers already know that bright but rare X-shaped galaxies, whose remarkable X-shaped jets arise from similar erratic behavior, behave similarly. The team behind the latest study suspects that the galaxy PBC J2333.9-2343 is also X-shaped: “We do not see an X-shape, but this could be explained because the new jets, by chance, are pointing in our direction,” the authors write in their study.
This study describes a paper (opens in new tab) Published March 20 in the journal Monthly Notices of the Royal Astronomical Society.
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