equation of time


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equation of time

n.
The difference between time measured from the observed position of the sun and time measured from the position of the mean sun, caused by changes in the earth's orbital speed through the cycle of the seasons. It is the difference between time measured with a sundial and time measured with a clock.

equation of time

n
(Horology) the difference between apparent solar time and mean solar time, being at a maximum in February (over 14 minutes) and November (over 16 minutes)

equa′tion of time′



n.
apparent time minus mean solar time, ranging from minus 14 minutes in February to over 16 minutes in November.
Translations
Zeitgleichung
References in classic literature ?
Captain Doane worked hard, pursuing the sun in its daily course through the sky, by the equation of time correcting its aberrations due to the earth's swinging around the great circle of its orbit, and charting Sumner lines innumerable, working assumed latitudes for position until his head grew dizzy.
An Open Edition of Equation of Time is scheduled to debut in early spring of 2016.
So we do customise -- for instance for the Equation of Time, we can customise the back-case, but we haven't done it up to now.
Immediately below both sundials there are two different graphs from which the Equation of Time can be read off as function of date, see Fig.
A limited edition of only 15, this timepiece is driven by the Calibre LUC 4TQE, a compendium of virtually every known complication: tourbillon, perpetual calendar, eight-day power reserve, large moon phases and equation of time.
The second correction is from the equation of time that takes into account the various perturbations in the earth's orbit and the rate of rotation that affect the time, the sun appears to cross the observer's meridian.
We also need to know two astronomical measures called the declination angle of the sun (5) and the real time-mean time difference, also known as the equation of time (T).
He thus became the first person in Le Locle to produce cylinder escapements, duplex escapements, perpetual calendar escapements and equation of time escapements.
It involves the somewhat complicated interplay of two astronomical measurements known as solar declination and the equation of time.