Subj : Daily APOD Report To : All From : Alan Ianson Date : Wed Mar 30 2022 00:15:40 Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2022 March 30 Animation: Odd Radio Circles Credits: Illustration: Sam Moorfield; Data: CSIRO, HST (HUDF), ESA, NASA; Image: J. English (U. Manitoba), EMU, MeerKAT, DES (CTIO); Text: Jayanne English Explanation: What do you call a cosmic puzzle that no one expected to see? In this case, Odd Radio Circles, aka ORCs. ORC-1 typifies the enigmatic five objects, only visible at radio frequencies, that were serendipitously discovered in 2019 using the new Australian SKA Pathfinder radio array. The final image in the featured video uses 2021 data from the South African MeerKAT array to reveal more detail. The radio data, assigned turquoise colors, are combined with a Dark Energy Survey optical/IR map. The animated artistCÇÖs illustration explores just one idea about the ORCsCÇÖ origins. If two supermassive black holes merge in the center of a galaxy, the associated shockwaves could generate rings of radio radiation. These grow to fill the video frame. The video zooms out so the expansion the ORC can be tracked until it is about a million light-years across. Fortunately, the up-coming Square Kilometer Array can help test this and other promising scenarios. Tomorrow's picture: open space __________________________________________________________________ Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U. --- BBBS/Li6 v4.10 Toy-6 * Origin: The Rusty MailBox - Penticton, BC Canada (1:153/757) .