mean sun


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mean sun

n.
A hypothetical sun defined as moving at a uniform rate along the celestial equator at the mean speed with which the real sun apparently moves along the ecliptic, used in computing the mean solar day.

mean sun

n
(Astronomy) an imaginary sun moving along the celestial equator at a constant rate and completing its annual course in the same time as the sun takes to move round the ecliptic at a varying rate. It is used in the measurement of mean solar time

mean′ sun′


n.
an imaginary sun moving uniformly in the celestial equator and taking the same time to make its annual circuit as the true sun does in the ecliptic.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.mean sun - a theoretical sun that moves along the celestial equator at a constant speed and completes its annual course in the same amount of time the real sun takes at variable speeds
framework, model, theoretical account - a hypothetical description of a complex entity or process; "the computer program was based on a model of the circulatory and respiratory systems"
References in periodicals archive ?
38%), even though the urban residents had a significantly higher mean sun exposure index (113 vs.
OR many people, holidays mean sun, sand and spending three hours blowing up plastic beach toys shaped like Lady Penelope's orangery.
Another approach uses the dynamical mean Sun or fictitious mean Sun - imaginary bodies that move along the ecliptic and the celestial equator, respectively, at a constant rate - and produces seasons of equal length.
The mean sun exposure index (hours per week of total body exposure with no sunscreen used) was 11.1 hours.
It could mean sun seekers will be confined to that small area as vegetation will be allowed to grow freely along the rest of the coastline.
By coincidence, the Maine rule gives a Blue Moon on February 19, 2000, using either the mean Sun or the apparent Sun.