Odd radio circles perplex astronomers

EarthSky ^ | March 23, 2022 | y Deborah Byrd

[BenLurkin]

Astronomers call it an odd radio circle or ORC. Astronomers have spotted only a handful of ORCs. They’re huge, about a million light-years across (16 times bigger than our Milky Way galaxy). Despite this, the ORCs are hard to see. They’re visible only at radio wavelengths. And, so far, they are unexplained. Since their discovery in 2019, astronomers have proposed different explanations for them, including galactic shockwaves, or the throats of wormholes. What are they?

Ray Norris from Western Sydney University and CSIRO, one of the authors on a new paper about ORCs, said only five odd radio circles have ever been revealed in space. Norris said in an article released March 21, on The Conversation:

"We can now see each ORC is centred on a galaxy too faint to be detected earlier. The circles are most likely enormous explosions of hot gas, about a million light years across, emanating from the central galaxy."

As of now, there are three leading theories to explain what causes ORCs:

– They could be the remnant of a huge explosion at the center of their host galaxy, like the merger of two supermassive black holes.

– They could be powerful jets of energetic particles spewing out of a galaxy’s center.

– They might be the result of a starburst “termination shock” from the production of stars in the galaxy.

[dsrtsage]

If you tune a receiver just right, you can faintly make out above the static “Sunday! Sunday! Sunday!”

[minnesota_bound]

Galactic smoke rings that make a galaxy look small.

[vpintheak]

LOL!