Meridian Line


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Meridian Line

 

the straight line along which the celestial meridian plane intersects the plane of the celestial horizon. The meridian line intersects the celestial sphere at the north and south points. The line in the horizontal plane perpendicular to the meridian line determines the east and west points on the celestial sphere. The sun reaches its greatest height above the horizon almost exactly at apparent noon, at. which point the center of its disk intersects the meridian, although the greatest height may be reached somewhat earlier or later than noon owing to variations in the declination of the sun. At this time, shadows cast by objects on the earth point along the meridian line and are at their shortest. This makes it possible to determine approximately the moment at which noon begins and the cardinal points—north, south, east, and west.

References in periodicals archive ?
In our previous work, reproducible fluorescence lines superimposable to meridian lines were revealed on the frontal interior abdominal wall when intracellular ROS indicators were injected into living SD-rats tail vein, confirming the substantial implication of ROS in meridian system [14].
At the north end, the meridian line climbs a stairway constructed to ascend at the angle of the north celestial pole.
Seasonal variation of the sun inclination and hence the longitudinal position on the meridian line sets the time over a year, in particular the extremities of the line, summer and winter solstices, and the equinoxes, spring and autumn.
The longitude of a position is determined by where its meridian line crosses the equator.
Within the Meridian line there is Aegean Sky and Aegean Mist, which offer parallel striping or checkerboard motifs on large and small square plates; Cascade Platinum, a simple banded pattern that introduces color through its accent plate and also offers square plates with a larger checkerboard design; and Cellini Platinum, featuring an alternating checkerboard rim design in black and chrome.
And of course the main reason why tourists come and visit is to see the meridian line which runs across the Observatory courtyard.
"The most powerful and precise way to measure that cycle was to lay out a 'meridian line' (usually a rod embedded in a floor) from south to north in a large dark building, put a small hole in the building's roof or facade, and then observe how many days the sun's noon image took to return to the same spot on the line." Cathedrals were the most convenient large, dark buildings available, and over the centuries they were turned into solar observatories throughout Europe, says Heilbron.
Organisers plan that the last of the beacons will be lit along the Meridian line at midnight.
The packs focus on environmental issues in countries along the meridian line including fair trade in Ghana, water management in Mall, and the threat facing the nomadic peoples of, among others, Burkina Faso and northern Ghana.
The county's east and west moments from the meridian line are similarly derived.
If you need to build up an appetite then take the steep walk up to the Royal Observatory where you can stand on the Meridian Line, popular with tourists and locals alike.
The aperture permits a pinhole image of the Sun to cross the meridian line each day at local noon, and the point where the sunlight intercepts it depends on the noon elevation of the Sun.