Astronomers have discovered a rare galaxy, dubbed the “Bullseye,” featuring nine star-filled rings after an interloper galaxy shot through its center. The discovery was made using NASA’s Hubble Space Telescope and data from the W.M. Keck Observatory in Hawaii. The Bullseye galaxy is approximately 250,000 light-years across, almost twice as large as our Milky Way galaxy.
The team identified eight visible rings, more than previously detected by any telescope in any galaxy, and confirmed a ninth using Hubble’s images. They also found evidence of the blue dwarf galaxy that caused the collision, which traveled like a dart through the Bullseye’s core about 50 million years ago.
Rings formed when gas was carried outward and mixed with dust to form new stars. The first two rings emerged quickly, while additional rings were staggered in formation due to the impact. Individual stars’ orbits remained largely undisturbed, but groups of stars bunched together to form distinguishable rings over millions of years.
The discovery provides a rare opportunity for astronomers to study galaxy evolution and potentially improve models predicting future events. Researchers expect that future telescopes, such as NASA’s Nancy Grace Roman Space Telescope, will reveal more galaxies like the Bullseye in the near future.
Source: https://science.nasa.gov/missions/hubble/hubble-investigates-galaxy-with-nine-rings