Speed of light is a featured article; it (or a previous version of it) has been identified as one of the best articles produced by the Wikipedia community. Even so, if you can update or improve it, please do so.
	This article appeared on Wikipedia's Main Page as Today's featured article on October 29, 2004, and on August 16, 2022.
Article milestones Date Process Result August 17, 2004 Featured article candidate Promoted December 7, 2008 Featured article review Demoted November 21, 2009 Peer review Reviewed January 25, 2010 Featured article candidate Not promoted October 12, 2010 Peer review Reviewed December 20, 2010 Featured article candidate Promoted March 19, 2022 Featured article review Kept Current status: Featured article

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I think the Michelson-Morley experiments should be added in this wiki. Please adivse. 82.174.79.67 ( talk) 21:40, 1 July 2023 (UTC) reply

See Speed_of_light#"Luminiferous_aether" Headbomb { t · c · p · b} 22:04, 1 July 2023 (UTC) reply

The speed of light is approximately 300,000 kilometres per second; 186,000 miles per second; 671 million miles per hour. The metric measurement should include 1.08 billion kilometres per hour, to be consistent with metric and imperial examples. Eiger3970 ( talk) 07:36, 5 September 2023 (UTC) reply

Quote:

Connections with electromagnetism

In the 19th century Hippolyte Fizeau developed a method to determine the speed of light based on time-of-flight measurements on Earth and reported a value of 315000 km/s (704,634,932 m/h).

His method was improved upon by Léon Foucault who obtained a value of 298000 km/s (666,607,015 m/h) in 1862. Kailandosk ( talk) 01:06, 18 November 2023 (UTC) reply

Are you suggesting our article may not be correct or proposing that it include conversions to km/h at that point, and in either case, why? NebY ( talk) 11:07, 18 November 2023 (UTC) reply

There's a definite discrepancy in number of significant digits between the quoted metric and traditional measurements... AnonMoos ( talk) 13:10, 18 November 2023 (UTC) reply

Indeed, but the values in parentheses aren't in the article. If we wanted to include them, we could use {{ Convert}}, which would probably round them appropriately automatically, and wouldn't abbreviate miles to "m" either, but I don't see why we'd want to include such conversions in that part of the article anyway. NebY ( talk) 13:46, 18 November 2023 (UTC) reply

I added the parenthesis. It's just a conversion to m/h that I made, just to show how different they are & to convert it into U.S. terms. Kailandosk ( talk) 00:15, 24 December 2023 (UTC) reply

I'm not sure if 315000 or 298000 km/s is correct. I feel it's 315000 km/s, but I'm not sure. Kailandosk ( talk) 18:04, 25 November 2023 (UTC) reply

186282.3970512 mi/s, to be fairly accurate.