Astronomers have uncovered a hidden realm of faint, circular cosmic structures—dubbed the “ghosts of the radio universe”—using powerful new radio telescopes like ASKAP in Australia and MeerKAT in South Africa. Through the EMU (Evolutionary Map of the Universe) survey, these instruments are revealing a “low surface brightness universe” filled with elusive objects such as supernova remnants, unstable Wolf-Rayet stars, and mysterious Odd Radio Circles (ORCs). These ghostly forms, often invisible in optical light, offer rare insights into stellar life cycles, galactic environments, and the energetic processes shaping the cosmos. Currently, the EMU survey using ASKAP is only partially complete (25%), many more discoveries are expected as astronomers continue mapping the southern sky in unprecedented detail.

The image above shows some of the objects captured by ASKAP. Author provided.