It’s been almost 80 years since British astronomer Frank Watson Dyson passed away. But the people of Great Britain are reminded of his accomplishments every day. Some BBC Radio stations broadcast a set of six tones every hour — the “six pips.” The final tone marks the top of the hour — a precise time signal that was important to the nation in the days before electronic clocks. The system was instituted by Dyson.

Dyson was born 150 years ago today, in Leicestershire. He became an astronomer at the Royal Greenwich Observatory at age 26, and its director — England’s Astronomer Royal — in 1910 — a post he held for 23 years.

Dyson studied the Sun and the structure of the Milky Way. And he organized two historic eclipse expeditions in 1919. As the Sun vanished from view, the expeditions measured a slight shift in the positions of stars near the Sun. That confirmed a prediction of Albert Einstein’s theory of gravity. The discovery made Einstein an international star, and led to wide acceptance of his theory.

In the 1920s, Dyson began organizing signals to transmit the precise Greenwich Mean Time — the international time standard. The signals were beamed out every quarter-hour through a radio station operated by the Post Office. And in 1924, he arranged to transmit the signals to the BBC, which in turn broadcast them to the nation and, eventually, the world — six “pips” that helped keep Britain on time for decades.

Script by Damond Benningfield