Whose experiment measured the speed of light?

In 1676 the Danish astronomer Ole Romer realised that the timing of eclipses of Jupiter moons varied depending on how far Earth was from Jupiter, and he used this to conclude that light travels at a finite speed. His estimate was rough but revolutionary, as many had thought light travelled instantly. Over the following centuries, scientists refined the measurement. In the late 19th and early 20th centuries, Albert Michelson made extremely precise measurements using mirrors and rotating apparatus. The modern value of the speed of light in a vacuum is about 299,792 kilometres per second.