Mean Sun definition of Mean Sun in the Free Online Encyclopedia.

mean sun [′mēn ′sən]

(astronomy)

A fictitious sun conceived to move eastward along the celestial equator at a rate that provides a uniform measure of time equal to the average apparent time; used as a reference for reckoning time, such as mean time or zone time.

Mean Sun

a fictitious point on the celestial sphere that moves uniformly along the celestial equator and crosses the vernal equinox at intervals of a tropical year. The mean sun is used in measuring mean solar time. The concept of the mean sun was introduced in the 18th century to make the measurement of daily time more accurate.

Owing to the eccentricity of the earth’s orbit and the obliquity of the ecliptic, along which the apparent annual motion of the sun occurs, the length of the apparent, or true, solar day—that is, the time interval between successive upper transits of the apparent, or true, sun—varies by as much as 50 seconds in the course of a year. The concept of the mean sun was introduced to eliminate this lack of uniformity. What is known as the equation of time is taken into account when determining mean solar time from observations of the sun. The equation of time is the difference between the right ascensions of the apparent sun and the mean sun. Alternatively, the equation of time can be defined as the difference between the hour angles of the apparent and mean suns.

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No references found	38%), even though the urban residents had a significantly higher mean sun exposure index (113 vs. Air pollution and vitamin D deficiency by Gaby, Alan R. / Townsend Letter Byline: Shereen Lowe SUMMER might mean sun, sea and sand, but it also means our ears have to suffer the onslaught of infectious novelty songs that get playedeverywhere PREPARE FOR DJ DAZ The Woah Song Daz Sampson, one half of Uniting Nations, strikes out on his own with this party anthem. Music: Summer's here s it's time to cover your ears; Shereen Lowe ... by Daily Post (Liverpool, England)	mean normal stress mean place mean point of impact mean point of impact error Mean Position mean power mean pressure mean profile Mean Proportional mean range mean rank method mean rise interval mean rise of tide mean river level mean sea level mean sidereal time mean solar day mean solar second Mean Solar Time mean specific heat mean spherical intensity mean spring range mean spring rise mean square mean stress Mean Sun mean temperature mean temperature difference mean terms mean tide mean tide level mean time mean time between failures Mean Time Between Faults mean time to failure Mean Time To Recovery mean time to repair mean trajectory Mean Value Mean Value Theorem mean velocity mean water level mean, median, and mode mean-average boiling point mean-square deviation mean-square error mean-square velocity mean-square-error criterion Mean-Time Clock mean-time screw mean-tone scale	mean square mean square mean square Mean Square Angular Error mean square deviation Mean Square Displacement Mean square error Mean Square Error Method Mean Square Error of Prediction Mean Square Error Selection Criteria Mean Square Estimation Error Mean Square of Weighted Deviates Mean Square Prediction Error Mean Square Voltage Mean squared error Mean Squared Error of Cross-Validation Mean Squared Positional Error Mean squared prediction error Mean Squared Systolic Peak Frequency Mean Stem Unit Length Mean Streak Mean Street Posse mean stress Mean Sub-Sequence-Reduced Mean Subject Grade Mean Summer SCRIM Mean Sun mean suns mean suns Mean Superior Mesenteric Artery Blood Flow Mean Supply Downtime Mean Supply Response Time Mean Swaps Between Failure Mean Systemic Filing Pressure Mean Systolic Blood Pressure Mean Systolic Ejection Rate Mean Systolic Ejection Rate Index Mean Systolic Inferior Wall Velocity Mean Systolic Wall Thickening Velocity mean temperature Mean Temperature and Pressure mean temperature difference Mean Temperature of the Coldest Month Mean Temperature of the Warmest Month mean term Mean Terminal Bronchial Density mean terms Mean Testicular Biopsy Score Mean Texture Depth Mean Therapeutic Dose Mean Thickness of Inner Retinal Layers Mean Tide Mean Tide

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38%), even though the urban residents had a significantly higher mean sun exposure index (113 vs.

Air pollution and vitamin D deficiency by Gaby, Alan R. / Townsend Letter

Byline: Shereen Lowe SUMMER might mean sun, sea and sand, but it also means our ears have to suffer the onslaught of infectious novelty songs that get playedeverywhere PREPARE FOR DJ DAZ The Woah Song Daz Sampson, one half of Uniting Nations, strikes out on his own with this party anthem.

Music: Summer's here s it's time to cover your ears; Shereen Lowe ... by Daily Post (Liverpool, England)

mean normal stress

mean place

mean point of impact

mean point of impact error