Dec 07, 2016
340th Anniversary of the Determination of the Speed of Light
This Doodle’s Key Themes
While working in the Royal Observatory in Paris in 1667, Danish astronomer Ole Rømer discovered that the speed at which light travels could be measured. His theory built on earlier ideas by Galileo, and the observance of how the timings between Jupiter’s moon eclipses changed depending on its distance from the Earth. His theories gained support from other great scientific minds of the time, including Isaac Newton and Edmond Halley.
Rømer also made significant contributions to Copenhagen, where he spent his later years, having introduced oil lamp street lighting and proper sewers to the city. Another achievement includes the invention of the mercury thermometer in 1709, which was said to have inspired Daniel Gabriel Fahrenheit to invent the temperature scale still in use today.
Today’s Doodle shows Rømer hard at work in his observatory 340 years ago.
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