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latitude,angular distance of any point on the surface of the earth north or south of the equator. The equator is latitude 0°, and the North Pole and South Pole are latitudes 90°N and 90°S, respectively. The length of one degree of latitude averages about 69 mi (110 km); it increases slightly from the equator to the poles as a result of the earth's polar flattening. Latitude is commonly determined by means of a sextantsextant,
instrument for measuring the altitude of the sun or another celestial body; such measurements can then be used to determine the observer's geographical position or for other navigational, surveying, or astronomical applications.
..... Click the link for more information. or other instrument that measures the angle between the horizon and the sun or another celestial body, such as the North Star (see PolarisPolaris
or North Star,
star nearest the north celestial pole (see equatorial coordinate system). It is in the constellation Ursa Minor (see Ursa Major and Ursa Minor; Bayer designation Alpha Ursae Minoris) and marks the end of the handle of the Little Dipper.
..... Click the link for more information. ). The latitude is then found by means of tables that give the position of the sun and other bodies for that date and hour. An imaginary line on the earth's surface connecting all points equidistant from the equator (and thus at the same latitude) is called a parallel of latitude. On most globes and maps parallels are usually shown in multiples of 5°. Because of their special meanings, four fractional parallels are also shown. These are the Tropic of Cancer (23 1-2°N) and the Tropic of Capricorn (23 1-2°S), marking the farthest points north and south of the equator where the sun's rays fall vertically (see tropicstropics,
also called tropical zone or torrid zone, all the land and water of the earth situated between the Tropic of Cancer at lat. 23 1-2°N and the Tropic of Capricorn at lat. 23 1-2°S.
..... Click the link for more information. ), and the Arctic CircleArctic Circle,
imaginary circle on the surface of the earth at 66 1-2°N latitude, i.e., 23 1-2° south of the North Pole. It marks the northernmost point at which the sun can be seen at the winter solstice (about Dec.
..... Click the link for more information. (66 1-2°N) and the Antarctic CircleAntarctic Circle,
imaginary circle on the surface of the earth at 66 1-2°S lat., i.e., 23 1-2° north of the South Pole. It marks the southernmost point at which the sun can be seen at the winter solstice (about June 22) and the northernmost point of the southern polar
..... Click the link for more information. (66 1-2°S), marking the farthest points north and south of the equator where the sun appears above the horizon each day of the year (see also midnight sunmidnight sun,
phenomenon in which the sun remains visible in the sky continuously for 24 hr or longer, occurring only in the polar regions. The midnight sun is due to the fact that the plane of the earth's equator is tilted about 23 1-2° to the plane of the ecliptic (the
..... Click the link for more information. ). Parallels of latitude and meridians of longitudelongitude
, angular distance on the earth's surface measured along any latitude line such as the equator east or west of the prime meridian. A meridian of longitude is an imaginary line on the earth's surface from pole to pole; two opposite meridians form a great circle dividing
..... Click the link for more information. together form a grid by which any point on the earth's surface can be specified. The term latitude is also used in various celestial coordinate systems (see ecliptic coordinate systemecliptic coordinate system,
an astronomical coordinate system in which the principal coordinate axis is the ecliptic, the apparent path of the sun through the heavens. The ecliptic poles are the two points at which a line perpendicular to the plane of the ecliptic through the
..... Click the link for more information. ).
Latitude(religion, spiritualism, and occult)
Latitude (properly called terrestrial latitude) refers to a location’s distance from the equator. Celestial latitude refers to the angular distance (distance measured in degrees and minutes of an arc) that a planet or other celestial body is located above or below the ecliptic. One can also talk about galactic latitude, which is the distance above or below a plane drawn through the center of the Milky Way, as well as heliographic latitude, which is the distance north or south of the Sun’s equator. Clearly, the notion of latitude can be extended to any celestial body.
one of the coordinates in numerous systems of spherical coordinates that determine the position of points on the earth’s surface (seeGEOGRAPHIC COORDINATES and COORDINATES [in geodesy]), on the celestial sphere (seeCELESTIAL COORDINATES), or on the surface of the sun, moon, and planets (see HELIOCENTRIC COORDINATES; SELENOGRAPHIC COORDINATES;and PLANETOGRAPHIC COORDINATES).
For the earth, a distinction is made between astronomical latitude and geodetic latitude (or geographical latitude), depending on the method of determination. The astronomical latitude ϕ of a point on the surface of the earth is equal to the angle between a plumb line (normal to the geoid) to the point and the plane of the earth’s equator. It is also equal to the height of the pole of the earth above the horizon and is considered to be positive in the northern hemisphere and negative in the southern hemisphere. The latitude of points on the equator is 0°; the latitude of the north pole is + 90°, and that of the south pole, –90°. Lines with the same values of ϕ are parallels.
Unlike astronomical latitude, which is determined from astronomical observations, geodetic latitude is computed on the basis of measurements on the earth’s surface, for example, by the triangulation method, taken between the point being measured and a certain starting point. Geodetic latitude is equal to the angle formed by the normal to the reference ellipsoid passing through the given point and the plane of its equator.
The geocentric latitude ϕ′ is equal to the angle between the radius drawn from the center of the earth’s ellipsoid to the given point and the plane of the equator. There is a relationship between astronomical latitude and geocentric latitude: tan ϕ′ = (bla)2 tan ϕ, where a is the semimajor axis of the earth’s ellipsoid and b is the semiminor axis. The largest difference between ϕ and ϕ’ occurs when ϕ = 45° (Δϕ ≃ 11′5); at the equator and the poles, Δϕ = 0.
In geodesy, the reduced latitude u is also used, whose values lie between ϕ and ϕ’ and are determined by the formula tan u = (bla)tan ϕ.
A. A. MIKHAILOV
ii. That property of a film that enables it to accommodate varying conditions of light without adversely affecting the resultant photograph.
latitudeThe location north or south of the equator, measured in degrees from the equator, which is 0. The North Pole is plus 90 degrees, and the South Pole is minus 90 degrees. Degrees are further divided into minutes and seconds.
Longitude is the location east and west of the Greenwich prime meridian in London, measured in degrees from this reference point, which is 0. Europe is plus degrees to the east, and the Americas are minus degrees to the west.
To pinpoint a location on earth, the north/south latitude (y-axis) is combined with the east/west longitude (x-axis). For example, the Empire State Building in New York is expressed in degrees, minutes and seconds as follows: