Bizarre gigantic space circle captured by astronomers in unprecedented detail

Amazing stuff! What else is out there in space?

"Astronomers have captured a close-up image of a rare and mysterious space object, prompting a renewed push to discover its origin. Odd radio circles (ORCs) are gigantic rings of radio waves. Only five have ever been sighted, and never in such spectacular detail.

The image of ORC J2103-6200, also called ORC1, was captured by the high-resolution MeerKAT radio telescope in South Africa ...
The new MeerKAT radio data shows that the ORC’s large outer circle is possibly more than a million light years across, ten times the diameter of the Milky Way, with a series of smaller rings inside. ...
The first three ORCs, including ORC1, were discovered using the Australian Square Kilometre Array Pathfinder (ASKAP) telescope in 2019. A fourth was identified in archival data from India’s Giant MetreWave Radio Telescope in 2013, and a fifth was discovered by Koribalski in newer ASKAP data last year. Most of the ORCs have a galaxy at their centre, which astronomers suggest might have something to do with their creation. Also puzzling to scientists is the fact that ORCs have been spied only in radio wavelengths and have not been detected by optical or X-ray telescopes. ..."

From the abstract:

"Odd Radio Circles (ORCs) are recently-discovered faint diffuse circles of radio emission, of unknown cause, surrounding galaxies at moderate redshift ($z ~ 0.2-0.6). Here we present detailed new MeerKAT radio images at 1284 MHz of the first ORC, originally discovered with the Australian Square Kilometre Array Pathfinder, with higher resolution (6 arcsec) and sensitivity (~ 2.4 uJy/bm).

In addition to the new images, which reveal a complex internal structure consisting of multiple arcs, we also present polarisation and spectral index maps. Based on these new data, we consider potential mechanisms that may generate the ORCs."

Bizarre space circle captured in unprecedented detail Astronomers have sighted only a handful of odd radio circles, and are trying to pin down what causes them.

MeerKAT uncovers the physics of an Odd Radio Circle (open access, preprint)