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Equation of Time

Astronomy Equation of the centreEquator

Equation of time
From LoveToKnow 1911
EQUATION OF TIME, the difference between apparent time, determined by the meridian passage of the real sun, and mean time, determined by the passage of the mean sun.

 


Equation Of Time
Related Category: Astronomy: General
see solar time.
More on Equation Of Time
Solar Time - time defined by the position of the sun. The solar day is the time it takes for the sun to return to the same meridian in the sky.

Equation of Time
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Equation of Time The difference between apparent and mean solar time.
Equinox The two times of the year when the Sun crosses the celestial equator; vernal or spring equinox occurs about March 21st, ...

Equation of Time
(a) The difference between Apparent and Mean Solar Time. At Greenwich, apparent Solar noon varies between 11h44m05s and 12h14m19s. Maximum contribution from Earth's orbital eccentricity, ~ 8 min; from Earth's obliquity, ~ 10 min.

Equation of Time: [E, EoT] the time difference between Local Apparent Time (apparent solar time) and mean solar time at the same location. Its value varies between extremes of about +14 minutes in February and -16 minutes in October.

See equation of time for an in-depth description of the east-west characteristics of the analemma.
[edit] Other analemmas
The analemma for Mars ...

(186) The equation of time
(216) Why are the two daily tides unequal?
(304) Can the heat of sunshine make the Earth expand?

What is the equation of time?
What is solar time?
How do navigators use the equation of time?
Where is the mean sun?
Wmat makes up the atmosphere on Mars?
Who was Cleomedes?
What made Cleomedes famous?

equation of time Prior to 1965, the difference between mean time and apparent time, usually labeled + or - as it is to be applied to mean time to obtain apparent time.

The difference between mean and apparent time is called equation of time.

This is due to the variable speed of the Earth in its orbit, and is described as the equation of time. It has different values for the March and the September equinox (+8 and âˆ'8 minutes respectively).

A stretched figure-eight curve obtained if solar declination is plotted against the equation of time throughout a whole year.

Time, Local Mean (LMT):
Solar time for a given location reduced from apparent to mean by application of the equation of time. Also called Local Solar Time.

Firstly the dial itself can be rotated to allow for the equation of time. The maximum daily change is only half a minute. It should be noted that the longitude correction is also allowed for by a similar one--off adjustment.

(b) An equation that describes a relationship between the energy, pressure, and density of a quantity of mass. The equation of state of a substance depends on the material it is made of and on the forces operating within it. [LB90] Equation of Time ...

See also: Time, Orbit, Solar, Earth, Sun