A team of astronomers has made the first-ever observation of two galaxies engaging in a cosmic “duel.” The galaxies are hurtling towards each other at an incredible 1.1 million miles per hour, with one galaxy using its intense beams of radiation to weaken the other.
The observation was made using combined data from ground-based telescopes over nearly four years and provides a rare glimpse into earlier times in the universe when star formation and galaxy mergers were more common. The galaxies are part of a larger merger that occurred 11 billion light-years ago, with the collision still visible today.
At the center of the “attacking” galaxy is a quasar, powered by a supermassive black hole. This powerful radiation beam disperses gas clouds and weakens the opposing galaxy’s ability to form new stars. The study also reveals that the quasar’s ultraviolet waves are about 1,000 times stronger than those emitted by our Milky Way.
While researchers observed that the clouds were not dense enough to create new stars after being dispersed, additional material from the victim galaxy eventually fuels the quasar with more energy, potentially allowing molecular clouds to reform. This discovery confirms a long-held theory and provides insight into earlier times in the universe when star formation and galaxy mergers were more common.
Galaxy mergers, like the observed “cosmic joust,” are still relatively rare events but have occurred throughout the universe’s history. The study highlights the importance of continued research into these phenomena to better understand the birth and evolution of new galaxies.
Source: https://wtop.com/science/2025/05/galaxies-battle-in-cosmic-joust-witnessed-by-astronomers-for-the-first-time