What happened
Starting in 1998, puzzling signals appeared in data from Australia’s Parkes radio telescope: pulses lasting from a few to several tens of milliseconds, whose frequency swept downward over time much like fast radio bursts from distant galaxies. What set them apart was that they appeared simultaneously in many of the receiver’s beams, indicating a source close to Earth. In 2011 astronomers named them “perytons,” after a mythical creature – a deer that casts the shadow of a man. Lightning and other natural phenomena were considered, and the puzzle cast doubt on the credibility of discoveries of genuine bursts. The breakthrough came in 2015, when a new receiver made it possible to detect interference accompanying the perytons at a frequency of about 2.4 GHz, typical of microwave ovens.
Witnesses
Teams of astronomers working with data from the Parkes radio telescope; the mystery was solved in 2015 by a group led by Emily Petroff.
Explanations and hypotheses
Researchers established that perytons were produced when someone opened the door of a microwave oven in the observatory building before it had finished running – the magnetron then emitted a brief pulse that was picked up by the telescope when it was pointed at the right angle. The signals were reproduced experimentally. The explanation did not undermine the authenticity of genuine fast radio bursts, which come from space.
Explained The phenomenon has a widely accepted, down-to-earth explanation.
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