An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



Number of Results: 16 Search : latitude
astronomical latitude
  ورونای ِ اخترشناسیک   
varunâ-ye axtaršenâsik

Fr.: latitude astronomique   

The angle between the → equatorial plane and the true → vertical at a point on the surface.

astronomical; → latitude.

celestial latitude
  ورونای ِ آسمانی   
varunâ-ye âsmâni

Fr.: latitude céleste   

Angular distance → north or → south measured from the → ecliptic to a → celestial object.

celestial; → latitude.

circle of latitude
  پرهون ِ ورونا   
parhun-e varunâ

Fr.: parallèle   

1) A circle of the celestial sphere, parallel to the ecliptic.
2) A circle on the terrestrial surface parallel to the equator, along which longitude is measured.

circle; → latitude.


Fr.: colatitude   

The polar angle on a sphere measured from the north pole instead of the equator; equal to "90° - latitude".

co- + → latitude.

ecliptic latitude
  ورونای ِ هورپهی   
varunâ-ye hurpehi

Fr.: latitude écliptique   

One of the two coordinates in the → ecliptic system; the angle measured from the ecliptic, positive toward the north.

ecliptic; → latitude.

Galactic latitude
  ورونای ِ کهکشانی   
varunâ-ye kahkešâni

Fr.: latitude galactique   

In the → Galactic coordinate system, the angle between the line of sight to an object and the → Galactic equator. Galactic latitude, usually represented by the symbol bII, ranges from +90 degrees to -90 degrees.

galactic; → latitude.

geocentric latitude
  ورونای ِ زمین-مرکزی   
varunâ-ye zamin-markazi

Fr.: latitude géocentrique   

The angle between the geocentric location vector and the → geodetic equator.

geocentric; → latitude.

geodetic latitude
  ورونای ِ زمین‌سنجیک   
varunâ-ye zamin-sanjik

Fr.: latitude géodésique   

The → acute angle between the → geodetic vertical and the → geodetic equator.

geodetic; → latitude.

geographic latitude
  ورونای ِ زمین‌نگاریک   
varunâ-ye zaminnegârik

Fr.: latitude géographique   

A synonym for → geodetic latitude or → astronomical latitude.

geographic; → latitude.

high latitudes
  وَروناهای ِ بالا   
varunâhâ-ye bâlâ

Fr.: hautes latitudes   

The latitude belt roughly between 60 and 90 degrees North and South. Also referred to as the polar region.

high; → latitude.

horse latitudes
  وَروناهای ِ اسبی   
varunâhâ-ye asbi

Fr.: calmes tropicaux, latitudes des chevaux   

The belts of latitude over the oceans, located around 30° north and south of the equator, characterized by predominantly calm or light winds and hot and dry weather.

horse; → latitude.
The origin of the term horse latitudes is not clear, despite numerous speculations. A likely explanation appears in Spanish in a natural history text (Historia General y Natural de las Indias by Lopez de Gomara) published in 1535. Therefore, the term derives from El Golfo de las Yeguas, which translates to "The Mares' Sea." The sailors called it this because in the 1500's there was active shipping of horses, particularly brood mares, from Spain to the Canary Islands, and many of the horses died during the transit of this area.


Fr.: latitude   

The angle between a perpendicular at a location, and the → equatorial plane of the Earth. → longitude. See also:
astronomical latitude, → celestial latitude, → circle of latitude, → colatitude, → ecliptic latitude, → Galactic latitude, → geocentric latitude, → geodetic latitude, → geographic latitude, → high latitudes, → horse latitudes, → middle latitudes, → spherical latitude, → supergalactic latitude.

L. latitudo "breadth, width, size," from latus "wide," from PIE base *stela- "to spread" (cf. O.C.S. steljo "to spread out," Arm. lain "broad").

Varunâ, from var "breadth, side, breast," variant bar, Tabari vari "width," Mid.Pers. var "breast," Av. varah- "breast" (Sk. vara- "width, breadth") + -u a suffix forming adjectives; Av. vouru- "wide;" + -nâ a suffix of dimension.

libration in latitude
  هلازان ِ ورونایی   
halâzân-e varunâ-yi

Fr.: libration en latitude   

A tiny oscillating motion of the Moon arising from the fact that the Moon's axis is slightly inclined relative to the Earth's. More specifically, the Moon's polar axis is tilted nearly 7° with respect to the plane of its orbit around Earth. Hence for half of each orbit we see slightly more of the north pole when its tipped toward us, and for the other half we see slightly more of its south pole. Libration in latitude displaces the mean center of the Moon north-south by between 6°.5 and 6°.9.

libration; → latitude.

middle latitudes
  وَروناهای ِ میانی   
varunâhâ-ye miyâni

Fr.: latitudes moyennes   

The latitude belt roughly between 35 and 65 degrees North and South. Also referred to as the temperate region.

middle; → latitude.

spherical latitude
  ورونای ِ کره‌ای، ~ سپهری   
varunâ-ye kore-yi, ~ sepehri

Fr.: latitude sphérique   

The angle between the → normal to a spherical reference surface and the → equatorial plane.

spherical; → latitude.

supergalactic latitude
  ورونای ِ ابرکهکشانی   
varunâ-ye abarkahkašâni

Fr.: latitude supergalactique   

supergalactic coordinate system.

supergalactic; → latitude.