‘Odd radio circles’: 4 mysterious objects spotted in outer space suggest extragalactic activity

Something unknown is floating around in outer space. Astronomers have discovered four mysterious objects that appear to be circular and brighter along the edges, according to a recent study.

The study by astronomers reported the mysterious sighting of the four ring-shaped objects. Dubbed “odd radio circles,” or ORCS for short, the mysterious figures are speculated to be linked with distant galaxies.

The new paper outlines several theories for the creation of the ORCs that scientists and astronomers proposed, but none seem to exactly fit the bill for all four objects.

After ruling out objects like supernovas, planetary nebulas and star-forming galaxies, the astronomers speculated that the mysterious figures could represent a “spherical shock wave” from an extragalactic event or from a radio galaxy.

Kristine Spekkens, an astronomer at the Royal Military College of Canada and Queen’s University, who was not involved in the study, told Live Science that the objects may point to a new phenomenon that has not been probed yet.

"It may also be that these are an extension of a previously known class of objects that we haven't been able to explore."

“We also acknowledge the possibility that the ORCs may represent more than one phenomenon, and that they have been discovered simultaneously because they match the spatial frequency characteristics of the ASKAP (Australian Square Kilometre Array Pathfinder) observations,” the researching astronomers wrote in the study.

Australian astronomers in the study noted that the four objects were found while they were working on the Evolutionary Map of the Universe Pilot, an all-sky continuum survey. Three ORCs were discovered by visual inspections of the survey, while the fourth one was discovered in archival data taken with the Giant Metrewave Radio Telescope in March 2013.

The rarity of these objects, along with their low-surface brightness, made it unlikely that they could have been discovered in previous surveys.

The study was posted on the preprint website arXiv and has been submitted for review before publication to the journal Nature Astronomy.