Construct · 1 fields · 1 citations

equation of time: a standalone construct

One name. One construct. A landmark on the map.

● anchor · one construct, one field Nearest construct by meaning·not indexed
equationof time1 CONSTRUCTEquation of timeMEEUS · ALGORITHMS

A single standalone construct; nearby constructs are located against it in the Collider. Tap a field for its definition, unit, and measures.

Positional astronomy

Sundial time minus clock time

The equation of time is the difference, at any moment, between apparent solar time (the time a sundial shows) and mean solar time, the uniform time a clock keeps. It arises because the Sun's apparent daily motion is uneven: Earth's orbit is elliptical and its axis is tilted, so the real Sun runs ahead of or behind the fictitious "mean sun" by up to about a quarter of an hour over the year, tracing the figure-eight analemma. Meeus's Astronomical Algorithms gives the standard method for computing it. The referent is a time correction, measured in minutes, that reconciles sun time with clock time.[1]

Unit
The difference in minutes between apparent and mean solar time
Recovery means
Not applicable
Measured by
Computed from the Sun's position (obliquity and orbital eccentricity) and tabulated through the year

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Nearby constructs

clock2 fields · 2 citationsjingle · one word, two constructsmean3 fields · 6 citationsjingle · one word, three constructsaxis1 fields · 1 citationsanchor · a standalone construct

References

  1. Meeus, J. (1998). Astronomical algorithms (2nd ed.). Willmann-Bell. ISBN 9780943396613

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