How Did Galileo's Experiment Measure the Speed of Light?

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SUMMARY

Galileo's experiment to measure the speed of light involved two shrouded lamps placed on distant hilltops. When Galileo opened his lantern, his assistant would open his lamp upon seeing the light, allowing Galileo to measure the time taken for the light to travel between them. This early attempt was unsuccessful due to the high speed of light, which rendered the time difference too small to measure accurately. Modern measurements confirm that all colors of light travel at the same speed in a vacuum, a fact established over three centuries ago.

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Hello again, Here to ask a few more questions.
I previously asked a question about light and weather or not it could possibly have different speeds. But I recently realized that the burning of different chemicals can have different tones of light.

I would like to know how exactly we first measured how fast the speed of light was, what we used as a source, and if we could conduct an experiment using the light from different burning chemicals to find out if there is a different speed- or if it already has been done let me know.

Thanks
-Q?
 
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different colors of light all travel at the same speed in a vacuum (i.e. radio waves, x-rays, blue, red, etc.). The first decent record of the speed of light was done by observing the perceived lag in the orbit of jupiter. That was over 3 centuries ago. Now any child in a high school science lab (well, a high school science lab with good funding) can measure the speed of light to pretty high accuracy.
 
the first attempt at figuring out the speed of light was conducted by Galileo. Galileo and an assistant each took a shrouded lamp and stood within sight of each other on two widely-separated hilltops.

Galileo opened his lantern, and when the assistant saw its light, he opened his, too.

Galileo measured the time it took from when he opened his lantern to when he saw his assistant's lamp, which should be the time for light to travel back and forth between the two hilltops.

of course, due to light's high speed, his experiment epic failed.
 

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