When astronomers picked up the repeating signal, they scrambled into action. The signals, called perytons, started occurring on a regular basis, always around the same time of day. Could it be a signal from a distant extraterrestrial race? Was this the answer SETI has been looking for all these years? The answer, much to the disappointment of many, was far less dramatic and looked less like Close Encounters of the Third Kind and more like close encounters with hungry researchers.

The mysterious signals were first recorded in 1998 by scientists at Australia’s Parkes Observatory. The brief bursts of energy showed up repeatedly around noon. For seventeen years, scientists scratched their heads, trying to figure out the source and meaning of the signals.

At last, after exploring and discounting numerous explanations, the researchers landed on the explanation. The results of the exhaustive study were published in a scientific paper. If you are hoping the published findings will conclusively prove we are not alone in the universe, you will be sorely disappointed. The source of the mysterious signals was the microwave oven in the observatory’s break room.

The suspicious perytons showed up around noon because that’s when the hungry scientists ate lunch. If the microwave door was opened while it was still running, it triggered a brief burst of perytons that were interpreted by the radio telescope as a possibly-intelligent message.

Microwave ovens were not the first thing to perplex astronomers. In 1967, astronomers at France’s Haute-Provence Observatory thought they had discovered potassium flare stars. After much consideration, they reached the conclusion that the spectroscopic observations were probably caused by matches struck in the vicinity.

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