(FINANCIAL TIMES) - In 1928, Karl Jansky, a young radio engineer at Bell Telephone Laboratories, began researching static interference that might obscure voice transmissions. Five years later, after building a large rotating antenna and investigating every possibility he could think of, he published his remarkable conclusion: Some of the static was coming from the Milky Way.

His theory was eye-catching enough to be published in The New York Times, but scientists were unimpressed. Radio signals from outer space? Surely they were too weak to detect.