|Date||Investigator||Method||Result (km/s) (Error)|
|1849||Fizeau||Rotating toothed wheel||313,000 (5000)|
|1850||Foucault||Rotating mirror||298,000 (2000)|
|1875||Cornu||Rotating mirror||299,990 (200)|
|1880||Michelson||Rotating mirror||2990,910 (159)|
|1883||Newcomb||Rotating mirror||299,860 (30)|
|1928||Mittelstaedt||Kerr cell shutter||299,778 (10)|
|1932||Pease and Pearson||Rotating mirror||299,774 (2)|
|1940||Huttel||Kerr cell shutter||299,768 (10)|
|1951||Bergstrand||Kerr cell shutter||299,793.1 (0.3)
Reference: 'Introduction to Modern Optics, by Grant R. Fowles, Dover Publications, NYC, 1989, p6
Answered by: I would like to add that the speed of light has finally been defined to be 299 792 458 m/s, exactly. This is done since we believe c to be a true constant of nature. So, now, the definition of the meter is directly dependent on the definition
'In a way science is a key to the gates of heaven, and the same key opens the gates of hell, and we do not have any instructions as to which is which gate.
Shall we throw away the key and never have a way to enter the gates of heaven? Or shall we struggle with the problem of which is the best way to use the key?'
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