According to a publication in the Monthly Notices of the Royal Astronomical Society, this unusual structure is a rare “polar-ring galaxy” known as NCG 4632.
Differing from galaxies like our Milky Way, which consists of a bright disk of stars, this galaxy possesses a massive, eerie-looking ring that surrounds it. This ring is primarily composed of hydrogen gas and is tilted approximately 90 degrees relative to the galaxy’s plane.
The eye-shaped structure has been identified as a polar-ring galaxy – Image: Monthly Notices of the Royal Astronomical Society.
These striking eye-shaped structures may contain dust and stars and are believed to exist in only 1 in 1,000 galaxies. However, with the recent discoveries, a research team led by astronomer Nathan Deg from Queen’s University in Kingston, Canada, suggests that their occurrence rate may be up to 30 times higher.
During a survey using the ASKAP radio telescope in Western Australia, Dr. Deg and colleagues identified another similar structure surrounding the NGC 6156 galaxy.
The “polar-ring” of NCG 4632 is even more expansive, stretching up to 60,000 light-years. When combined with the galaxy’s central stellar disk, the ensemble resembles a colossal eye gazing directly at Earth.
These peculiar structures of polar-ring galaxies could provide insights into previously unknown aspects of how galaxies form and evolve in the universe. It remains a mystery why some galaxies have polar rings while most do not, according to Science News.
One hypothesis suggests that polar rings form during galaxy collision events.
To answer this question, astronomers need to seek out more of these polar-ring galaxies. However, identifying such “eye-shaped” galaxies proves challenging, as some distorted galaxies can also take on eye-like shapes but are not polar-ring galaxies.