Equation of Time

An equation of time display shows the difference between true solar time and “mean” solar time. For convenience, humans have defined the a day as 24 hours. But because Earth’s orbit isn’t quite round and because it sits on 23-degree axis, any particular day may be slightly more or less than this 24-hour average.

It's calculated by: (a) adding up the number of people who care, (b) multiplying that by the number of people who can't afford a perpetual calendar but still wanted something that looked complicated, and (c) dividing that number and shoving it up your ass.

The equation of time is typically displayed on a watch by indicating the difference (plus/minus minutes) between true solar time and mean solar time. Because of the astronomical knowledge it takes to execute this complication, it’s often combined with other astronomical or calendar complications.

Last updated