Home · On This Day · Sept. 26, 1950
Blue sun shines over England
Broadcast Date: Sept. 28, 1950
A woman nudges her friend and looks to the sky. "What colour does the sun look to you?" Both of them see what everyone else in Canada and parts of Europe saw that day: an indigo blue sun. A British radio announcer jokingly wonders if this is not "retribution descending on the universe for our atomic meddling," but soon reveals the scientific explanation. Smoke from B.C. forest fires has left particles in the air that interfere with the spectrum, letting only blue light through.At dusk, the phenomenon continues with a bright blue moon rising. The same radio announcer tells us he believes we're entitled to a blue moon now and then, "at least once in a blue moon."
Blue sun shines over England
• The forest fires in British Columbia burned on Sept. 23, 1950. A day later, the smoke that had reached Eastern Canada was thick enough to completely block out the sun. The following day, the sun was blue. By Sept. 26, the smoke had crossed the Atlantic.
• Volcanic eruptions and forest fires are known to cause a blue-looking sun or moon. The particles in the dust or smoke scatter the red end of the spectrum, leaving an excess of blue.
• After the eruption of Krakatoa, an island volcano in Indonesia, in 1883, blue moons and suns were widely observed.
• Astronomers have two definitions for the term "blue moon." One definition refers to when two full moons occur in one month. This happened twice in 1999. An older definition of blue moon is when four full moons occur in one season. The 500-year-old expression "once in a blue moon" is thought to predate the calendar meanings of the term.
Blue sun shines over England
Medium: Radio
Program: CBC Radio News
Broadcast Date: Sept. 28, 1950
Reporter: Gerard Fay
Duration: 2:11
Photo: NASA/Associated Press. This is a blue false-colour image captured by SECCHI/Extreme Ultraviolet Imaging Telescope in March 2007. It shows the sun's atmosphere at a temperature of 1 million degrees.
Last updated:
June 9, 2009









Blue sun shines over England.
The CBC Digital Archives Website.
Canadian Broadcasting Corporation.
Last updated: June 9, 2009.
[Page consulted on Feb. 16, 2012.]