MADRID, 6 (EUROPA PRESS)
Known as merger galaxy IIZw096, this luminous phenomenon is hidden by cosmic dust, but researchers first identified a bright, energetic light source 12 years ago.
“The James Webb Space Telescope has given us a completely new view of the universe thanks to its higher spatial resolution and infrared sensitivity,” Hanae Inami, author of the paper and associate professor at the Center for Astrophysics Sciences at the University of California, said in a statement. hiroshima. “We wanted to find the ‘engine’ that drives this merging galaxy system. We knew this source was deeply hidden by cosmic dust, so we couldn’t use visible or ultraviolet light to find it. Only in the mid-infrared, observed with the James Webb Space Telescope, we now see that this source dwarfs everything else in these merging galaxies.”
When galaxies merge, their stars, planets, and other components can crash into each other, the remains serving as fodder for new celestial episodes. Most of these galactic collisions emit only infrared light, which has longer wavelengths than light visible to humans and is beyond the range of human perception. In 2010, using the Spitzer Space Telescope, the same team discovered that the merging system was dominated by bright infrared emission. The researchers were able to measure the power of the engine – the source of the glow – but were unable to pinpoint its exact location due to the telescope’s limited resolution.
Using the James Webb Space Telescope, they found that this engine is responsible for most of the emission in the mid-infrared, which accounts for up to 70% of the system’s total infrared emission. They also found that the source has a radius of no more than 570 light-years, a tiny fraction of the size of the merging system, which is about 65,000 light-years across. This indicates that the energy is confined to a small space, according to co-author Thomas Bohn of Hiroshima University.
“It is intriguing that this compact source, far from the galactic centers, dominates the infrared luminosity of the system,” Bohn said.
According to Bohn, this source contributes significantly to the merger of galaxies despite being on the outskirts, like a speck of pepper in the white of a fried egg.
“We want to know what drives this source: is it a starburst or a massive black hole?” Inami asked. “We’ll use infrared spectra taken with the James Webb Space Telescope to investigate it. It’s also unusual for the ‘engine’ to be outside the main parts of merging galaxies, so we’ll explore how this powerful source ended up there.”
Jason Surace, from the California Institute of Technology and co-author of the study, says that this finding corroborates the most recent knowledge about the universe and its changes.
“The last few decades, fueled by new infrared observations made primarily from space, have shown that the universe is an amazingly dynamic and changing place,” says Surace. “In times past, it was thought that galaxies – the biggest things we knew of – were simply spinning around essentially unchanging, like celestial temples in the heavens.”
In addition to identifying the location of the engine, the researchers found 12 “clusters” of light. Some of them had already been detected by the Hubble Space Telescope in the near infrared, while another five were detected by the James Webb Space Telescope. According to Inami, they emit colors in the mid-infrared that suggest they are forming stars.
“The mid-infrared images from the James Webb Space Telescope described in this paper reveal a hidden aspect of the merging galaxy IIZw096 and open a door to the identification of sources heavily obscured by dust that cannot be detected at shorter wavelengths. Inami explains. “Future planned spectroscopic observations of IIZw096 will provide additional information about the nature of dust, ionized gas, and hot molecular gas in and around the perturbed region of this luminous merging galaxy.”
The study has been published in The Astrophysical Journal Letters.