The speed of light:
A)was first accurately determined by Galileo in an experiment involving lanterns and shutters.
B)can be determined by observing the motions of the moons of Jupiter.
C)was not determined until the advent of lasers in 1960.
D)is too high to measure and consequently is still unknown.

Question

Quizplus · Accepted Answer

The speed of light can be determined by observing the motions of the moons of Jupiter. This was first done by Danish astronomer Ole Rømer in the late 17th century.

The Speed of Light