History
| 1675 | Rømer and Huygens, moons of Jupiter | 220,000 |
| 1729 | James Bradley, aberration of light | 301,000 |
| 1849 | Hippolyte Fizeau, toothed wheel | 315,000 |
| 1862 | Léon Foucault, rotating mirror | 298,000±500 |
| 1907 | Rosa and Dorsey, EM constants | 299,710±30 |
| 1926 | Albert Michelson, rotating mirror | 299,796±4 |
| 1950 | Essen and Gordon-Smith, cavity resonator | 299,792.5±3.0 |
| 1958 | K.D. Froome, radio interferometry | 299,792.50±0.10 |
| 1972 | Evenson et al., laser interferometry | 299,792.4562±0.0011 |
| 1983 | 17th CGPM, definition of the metre | 299,792.458 (exact) |
Until the early modern period, it was not known whether light travelled instantaneously or at a very fast finite speed. The first extant recorded examination of this subject was in ancient Greece. The ancient Greeks, Muslim scholars and classical European scientists long debated this until Rømer provided the first calculation of the speed of light. Einstein's Theory of Special Relativity concluded that the speed of light is constant regardless of one's frame of reference. Since then, scientists have provided increasingly accurate measurements.
Read more about this topic: Speed Of Light
Famous quotes containing the word history:
“History is the present. That’s why every generation writes it anew. But what most people think of as history is its end product, myth.”
—E.L. (Edgar Lawrence)
“Throughout the history of commercial life nobody has ever quite liked the commission man. His function is too vague, his presence always seems one too many, his profit looks too easy, and even when you admit that he has a necessary function, you feel that this function is, as it were, a personification of something that in an ethical society would not need to exist. If people could deal with one another honestly, they would not need agents.”
—Raymond Chandler (1888–1959)
“We are told that men protect us; that they are generous, even chivalric in their protection. Gentlemen, if your protectors were women, and they took all your property and your children, and paid you half as much for your work, though as well or better done than your own, would you think much of the chivalry which permitted you to sit in street-cars and picked up your pocket- handkerchief?”
—Mary B. Clay, U.S. suffragist. As quoted in History of Woman Suffrage, vol. 4, ch. 3, by Susan B. Anthony and Ida Husted Harper (1902)