Free Astronomy Magazine May-June 2024

MAY-JUNE 2024 scope picked up something no one had ever seen before: radio wave cir- cles so large they contained entire galaxies in their centers. As the astrophysics community tried to determine what these circles were, they also wanted to know why the circles were. Now a team led by Uni- versity of California San Diego Pro- fessor of Astronomy and Astro- physics Alison Coil believes they may have found the answer: the circles are shells formed by outflowing ga- lactic winds, possibly from massive by W. M. Keck Observatory Michelle Franklin − UC San Diego Uncovering the origin of the rare radio circles I t’s not every day astronomers say, “What is that?” After all, most ob- served astronomical phenomena are known: stars, planets, black holes and galaxies. But in 2019 the newly completed ASKAP (Australian Square Kilometer Array Pathfinder) tele-