Today in History is a daily newsletter from Britannica. (more) Today in History—February 27: The Discovery of Solar Radio Waves Written by Michele Metych Michele Metych is the lead editor for Today in History at Encyclopædia Britannica. Michele Metych Fact-checked by Britannica Editors Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree.... Britannica Editors Last updated Feb. 24, 2026 •History On this day in 1942 a British physicist made a monumental discovery…and couldn’t tell anyone. Today in History is a daily newsletter from Britannica.Encyclopædia Britannica, Inc. Want to learn more about what happened on February 27, or any other day of the year? Sign up to receive the newsletter in your inbox every morning. British radar equipment operating at 55–85 MHz was experiencing severe interference: strange, powerful signals that jammed their systems. This was the middle of...

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