Odd Radio Circles: Giant explosions in distant galaxies
Tue, 25 Nov
|Belrose
Join astronomer Ray Norris, discoverer of the Odd Radio Circles (ORCs), as he unpacks one of the universe’s strangest recent discoveries and the mystery that still surrounds it.


Time & Location
25 Nov 2025, 6:00 pm – 7:30 pm
Belrose, 146 Forest Way, Belrose NSW 2085, Australia
About the event
Uncovering the Mystery of the Odd Radio Circles
Six years ago, astronomers spotted something astonishing: faint, circular radio emissions in the sky—unlike anything seen before. Some doubted they were even real. Today, we know these enormous "Odd Radio Circles" (ORCs), each nearly a million light years wide, surround distant galaxies and may be the aftermath of colossal explosions. But what caused them?
There are now three leading theories to explain what causes ORCs:
They could be the remnant of a huge explosion at the centre of their host galaxy, like the merger of two supermassive black holes;
They could be powerful jets of energetic particles spewing out of the galaxy’s centre; or
They might be the result of a starburst ‘termination shock’ from the production of stars in the galaxy.
Places
General Admission
$20.00
+$0.50 ticket service fee
Total
$0.00