Speed of Light - Freaky Fzx Friday Introduction

A normal Fzx course rarely deals with the wonderful aspects of science discovered after the American Civil War.

I instituted Freaky Fzx Friday two years ago to give a bit of modern physics on a regular basis.

Todays topic - the speed of light.  Light is fast and difficult to measure.  After Galileo observed the moons of Jupiter, Roemer measured the speed of light using the orbit of Io in 1676.

Light travels at 186,000 miles every SECOND.  Ridiculous and far faster than Earth at at 65,000 miles per HOUR around the sun.

But by 1887, Michelson and Morley had precise instruments capable of measuring tiny differences in the speed of light.  They tried to detect the stationary background of space by comparing the speed of light parallel to and perpendicular to the motion of Earth around our Sun.

There was ZERO DIFFERENCE between the two speeds.  They checked their instruments and repeated the experiment to no avail.  It seemed that light has the same speed no matter its direction or the speed of the source..

Next time - Einstein's interpretation of the results.