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by Firehed 4903 days ago
Tracks a true solar day? Is there actually a scientific definition of when a day starts and ends? As far as I can tell skimming Wikipedia, it's simply 86400 seconds.

Certainly by my body clock, a "true solar day" is when I'm on DST.

1 comments

Midday GMT is defined to be when the mean sun is directly over the prime meridian.

("Mean sun" as opposed to "apparent sun" because of the Earth being a naturally occurring celestial object, rather than an idealised mathematical model. See http://en.wikipedia.org/wiki/Equation_of_time .)