⏰ when
When was the first successful measurement of the speed of light made?
Quick Answer
In 1676, Ole Rømer made the first convincing measurement from observations of Jupiter’s moon Io. He showed light travels at a finite speed.
The Full Story
Ole Rømer made the first convincing measurement of the speed of light in 1676 using eclipses of Jupiter’s moon Io. He noticed timing differences depending on Earth’s changing distance from Jupiter and inferred that light takes time to travel. This was a breakthrough because it showed light is not instantaneous. Later measurements refined the value, but Rømer’s result changed physics and astronomy.
Key Facts
1.Rømer’s measurement was in 1676
2.He used observations of Io’s eclipses
3.It proved light has a finite speed
YouTube Angle
Suggested video title for this topic:
"A moon of Jupiter helped humanity realize that light is not instant."
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