(GIST OF SCIENCE REPORTER) Bullseye Galaxy

(JUNE-2025)

Bullseye Galaxy

Context:

A team of international researchers recently discovered a galaxy with nine rings. They called it a serendipitous discovery because previous ringed galaxies have only displayed two or three rings at best.

Discovery and Characteristics of the Bullseye Galaxy

The presence of eight rings was confirmed using the Hubble Space Telescope.

Data from the W.M. Keck Observatory in Hawaii confirmed the existence of the ninth ring.
The galaxy is officially named LEDA 1313424 but is commonly known as the Bullseye Galaxy.
The Bullseye Galaxy is nearly 2.5 times larger than the Milky Way, with a diameter of 250,000 light-years.
Formation of Rings: About 50 million years ago, a blue dwarf galaxy passed directly through the center of a larger galaxy, sending ripple-like waves of gas that triggered star formation in ring patterns. The dwarf galaxy remains nearby, about 130,000 light-years away, still linked by a thin trail of gas.

Potential Evolution to a Giant Low Surface Brightness (GLSB) Galaxy

The Bullseye Galaxy also shows signs that it could one day evolve into a giant low surface brightness (GLSB) galaxy.
GLSB galaxies are considered important in the study of dark matter.

Low surface-brightness galaxies (LSBs) are characterised by:

A shortage of elements heavier than hydrogen and helium.
Very little star formation despite possessing large disks filled with hydrogen. This is described as a paradox that scientists cannot explain.
They are believed to be filled with dark matter, making them excellent study targets for this mysterious matter.
A more uniform distribution of mass near their centres, which contradicts the standard model of cosmology that predicts denser centres. This discrepancy is a challenge for scientists
GLSB galaxies are the largest type of LSBs.
Example: Malin 1, about 6.5 times wider than the Milky

Way and one of the largest spiral galaxies known. Scientific Implications of the Bullseye Galaxy

Opportunities for Research

Potential to observe direct evidence of a collisional ring galaxy evolving into a GLSB galaxy.
Insights into dark matter distribution through GLSB galaxy studies.

Unresolved Questions

Transition from ringed galaxy to GLSB galaxy remains theoretical.
Need for cosmological simulations to validate theories (e.g. rapid dark matter halo spin).