barâxt-e axtaršenâsik, ~ axtari
Fr.: objet astronomique
A naturally occurring physical entity or association that lies beyond the Earth's atmosphere and can be studied observationally. In other words, a gravitationally bound structure that is associated with a position in space, but may consist of multiple independent astronomical objects. A list of astronomical objects includes → planets, → asteroids, → comets, → stars, → nebulae, galaxies (→ galaxy), → galaxy clusters, → pulsars, and → black holes. Note that → celestial body, → celestial object, and → heavenly body are less technical terms for these entities.
nepâhesgâh-e axtaršenâsik, ~ axtaršenâxti
Fr.: observatoire astronomique
A building, place, or institution designed and equipped for making → observations of astronomical phenomena.
Fr.: réfraction astronomique
sit-e axtaršenâsik, ~ axtaršenâxti
Fr.: site astronomique
A certain place whose characteristics, as to location, altitude, atmospheric conditions, etc., make it appropriate for astronomical observations.
Fr.: table astronomique
One of a set of tables giving parameters used for calculations of positions of the Sun, the Moon, and the planets in particular in pre-telescopic astronomy. The oldest known astronomical tables are those of Ptolemy. In Modern astronomy it is usually replaced by the term → ephemeris. Same as → zij. See also → Toledan Tables, → Alfonsine Tables.
nimtâb-e axtaršenâsik, ~ axtarsnâxti
Fr.: crépuscule astronomique
The time between sunset or sunrise and the moment when the Sun's center lies 18° below the horizon. → civil twilight.
astronomical unit (au)
yekâ-ye axtaršenâsik, ~ axtaršenâxti (#)
Fr.: unité astronomique
1) A unit of length equal to 149 597 870 700 m exactly, with symbol "au"
(re-definition at the International Astronomical Union's 28th General
Assembly in Beijing, China, August 20-31). The astronomical unit equals
1.5813 × 10-5 → light-years and
4.8481 ×10-6 → parsecs.
The science of the celestial bodies and the Universe, dealing especially with the positions, dimensions, distribution, motion, chemical composition, energy, and evolution of celestial bodies and phenomena.
O.Fr. astronomie, from L. astronomia, from Gk. astronomia, from → astro- "star" + nomos "arranging, regulating," related to nemein "to deal out."
Axtaršenâsi, from axtar "star," → astro- + -šenâsi "knowledge" from šenâxtan "to know, to discern."
Fr.: physique des astroparicules
axtar-šidnegâri, šidnegâri-ye axtari
The photography of stars, other celestial bodies, and stellar fields.
axtar-šidsanji, šidsanji-ye axtari
The measurement of the intensity of light of celestial bodies.
Of or pertaining to → astrophysics.
Fr.: jet astrophysique
Fr.: objet astrophysique
A scientist who studies → astrophysics.
The branch of → astronomy that deals with the → physics of → celestial objects and the → Universe in general. It relies on the assumption that the → laws of physics apply everywhere in the Universe and throughout all time. See also → observational astrophysics, → theoretical astrophysics.
Astrophysics, from → astro- "star" + → physics. The first use of the term astrophysics has been attributed to Johann Karl Friedrich Zöllner (1834-1882) in 1865. He defined it as a coalescence of physics and chemistry with astronomy (History of Astronomy: An Encyclopedia, ed. John Lankford, Routledge, 1997).
Not having → symmetry.
Lack of symmetry; not symmetrical.
Gk. asymmetria "lack of proportion," from asymmetros "ill-proportioned," from → a- "not" + symmetros "commensurable, symmetrical."
Nâhamâmuni, from nâ- "not" +
hamâmuni "symmetry," from
ham- "together =
A straight line which is approached, but never reached, by an infinite branch of a curve, and which can be regarded as a line tangent to the curve at infinity.
Nâhamsâv, literally "not touching each other," from nâ- "not" + ham "with" (akin to Gk. syn-) + sâv, agent noun of sâvidan "to touch."
Of or pertaining to an → asymptote.