Mysterious radio signals detected emanating from Antarctica's ice have left particle physicists baffled. The pulses were detected by the Antarctic Impulsive Transient Antenna (ANITA)—an array of radio instruments flown high above the southernmost continent via air balloon.

A balloon-borne experiment over Antarctica, designed to detect cosmic radio waves, has instead picked up bizarre signals that appear to be coming from deep within the ice. These signals challenge our current understanding of particle physics, scientists say.