An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

   Homepage   
   


A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

<< < -gr alp ast atm bro cor ech ext gra hyd lit mor orb pha phi pho pho pho phy roo sol sph Ste ult > >>

Number of Results: 466 Search : pH
asthenosphere
  سست‌سپهر   
sostsepehr (#)

Fr.: asthénosphère   

A layer of soft, partly molten, rock in the → Earth's mantle, located at a depth of 100 to 250 km, over which the more rigid plates of the → lithosphere are in motion.

Asthenosphere, from Gk. asthenes "weak" + → sphere.

Sostsepehr, from sost "weak, tender" + sepehr, → sphere.

astrograph
  اخترنگار   
axtarnegâr (#)

Fr.: astrographe   

A photographic instrument with great light gathering power which is used to photograph a large field in a single exposure.

Astrograph, from → astro- + → graph.

Axtarnegâr, from axtar, → astro-, + -negâr, → -graph.

astroparticle physics
  فیزیک ِ اخترذره   
fizik-e axtar-šzarre

Fr.: physique des astroparicules   

The area of science which deals with → elementary particle and → high-energy phenomena in → astrophysics and → cosmology.

astro-; → particle; → physics.

astrophotography
  اختر‌شیدنگاری، شیدنگاری ِ اختری   
axtar-šidnegâri, šidnegâri-ye axtari

Fr.: astrophotographie   

The photography of stars, other celestial bodies, and stellar fields.

astro-, → photography.

astrophotometry
  اخترشیدسنجی، شیدسنجی ِ اختری   
axtar-šidsanji, šidsanji-ye axtari

Fr.: astrophotométrie   

The measurement of the intensity of light of celestial bodies.

Astrophotometry, from → astro- + → photometry.

Axtar-šidsanji, from axtar-, → astro-, + -šidsanji, → photometry.

astrophysical
  اخترفیزیکی   
axtarfiziki (#)

Fr.: astrophysiqie   

Of or pertaining to → astrophysics.

astrophysics + → -al

astrophysical jet
  شان ِ اخترفیزیکی   
šân-e axtarfiziki

Fr.: jet astrophysique   

A very fast moving, → collimated beam of → ionized gas at high temperatures associated with most classes of compact objects that spin and/or accrete matter from their surroundings, such as → protostars, → X-ray binary systems, and, at a larger scale, with → active galactic nuclei, → gamma-ray bursts, and → quasars. In general, jet sources host → accretion disks and are associated with → magnetic fields. Astrophysical jets, despite their different physical scales and power, are morphologically very similar, suggesting a common physical origin. For example, in one extreme, → active galactic nuclei jets have typical sizes ≥ 106 pc, velocities near that of light c, and parent sources (→ massive black holes) with masses 106-9  Msun and luminosities ~ 1043-48Lsun; while in the other extreme, → young stellar objects jets have typical sizes ≤ 1 pc, velocities ≤ 10-3 c, and emerge from low mass protostars with masses ~ 1 Msun and luminosities (0.1-2 × 104Lsun. Jets play an important → feedback role in the evolution of their host systems. See also: → jet launching.

astrophysical; → jet.

astrophysical object
  بر‌آخت ِ اخترفیزیکی   
barâxt-e axtarfiziki

Fr.: objet astrophysique   

An extraterrestrial → object whose physical properties and formation are studied in → astrophysics.

astrophysical; → object.

astrophysicist
  اخترفیزیکدان   
axtarfizikdân (#)

Fr.: astrophysicien   

A scientist who studies → astrophysics.

astro-; → physicist. The term astrophysicist was introduced by Greenwich astronomer Edwin Dunkin in 1869.

astrophysics
  اخترفیزیک   
axtarfizik (#)

Fr.: astrophysique   

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).

atmophile
  اتمودوست، هوادوست   
atmodust, havâdust

Fr.: atmophile   

atmophile element.

atmo-; → phile.

atmophile element
  بن‌پار ِ اتمودوست، ~ هوادوست، ~ گازدوست   
bonpâr-e atmodust, ~ havâdust, ~ goazdust

Fr.: élément atmophile   

In the → Goldschmidt classification, a → chemical element that is extremely → volatile, i.e., forms a gas or liquid at the surface of the Earth. The atmophile elements are usually concentrated in the terrestrial → atmosphere and → hydrosphere. They are → hydrogen (H), → carbon (C), → nitrogen (N), and → noble gas/qot>es, namely → helium (He), → neion (Ne), → argon (Ar), → krypton (Kr), → xenon (Xe), and → radon (Rn) (Pinti D.L., 2017, Atmophile Elements. In: White W. (eds) Encyclopedia of Geochemistry, Springer).

atmophile; → element.

atmosphere
  جو، هواسپهر   
javv (#), havâsepehr

Fr.: atmosphère   

1) The gaseous envelope surrounding a star, planet, or moon. Several solar system planets retain considerable atmospheres, due to their strong gravitational force. The gas motions in the planetary atmosphere, as a response to the heating, coupled with the rotation forces, generate the meteorological systems. The planetary satellites → Titan and → Triton also have atmospheres (M.S.: SDE).
2) A unit of pressure, called standard atmosphere, which is the pressure of air balanced by a column of mercury 76 cm high with a density of the mercury of 13.595 g/cm3 at normal acceleration of gravity. Such a column applies a pressure equal to its weight to each square cm, or 1.01325 x 106 dynes/cm2 = 1.01325 x 105 N/m2. Since this pressure is equal to 1.03323 kilograms of force per square centimeter, instead of it use is often made of the technical atmosphere (at), exactly equal to 1 kgf/cm2.

New L. atmosphaera, from Gk. atmos "vapor" + spharia "sphere."

Havâsepehr, from Mod.Pers. havâ, → air, + sepehr, → sphere. Javv "air, atmosphere," from Ar. jauw.

atmospheric
  جوی، هواسپهری   
javvi, havâsepehri (#)

Fr.: atmosphérique   

Pertaining to or existing in the atmosphere of an astronomical object such as a planet, moon, or star.

atmosphere; → -ic.

atmospheric absorption
  درشم ِ جوی   
daršam-e javvi

Fr.: absorption atmosphérique   

The absorption of → electromagnetic radiation in the → atmosphere mainly by → water vapor, → carbon dioxide, and oxygen. The atmosphere introduces two more limiting factors in → remote sensing: → atmospheric scattering and → atmospheric turbulence.

atmospheric; → absorption.

atmospheric circulation
  پرهونش ِ هواسپهری   
parhuneš-e havâsepehri

Fr.: circulation atmosphérique   

The large-scale movements of air around areas of high and low pressure whereby heat is distributed on the surface of the Earth. Atmospheric motion is driven by uneven heating of the planet. The atmosphere (and ocean) → transfers the excess heat from → tropics to → poles. The flow is determined by balance between → pressure gradients and the → Coriolis effect.

atmospheric; → circulation.

atmospheric dispersion
  پاشش ِ جوی   
pâšeš-e javvi

Fr.: dispersion atmosphérique   

The splitting of starlight into a spectrum in the atmosphere because the atmosphere acts as a refracting prism. This phenomenon brings about a practical problem for spectroscopic observations using a slit. → differential refraction; → atmospheric refraction.

atmospheric; → dispersion.

atmospheric emission
  گسیل ِ جوی   
gosil-e javvi

Fr.: émission atmosphérique   

The emission of electromagnetic radiation from the atmosphere due to thermal and → non-thermal processes. → Thermal emission comes mainly from → water vapor. Non-thermal processes result in emission lines oxygen (optical) and OH (near-IR). Atmospheric emission is a very significant source of noise in astronomical observations. See also → airglow, → aurora.

atmospheric; → emission.

atmospheric extinction
  خاموشی ِ جوی   
xâmuši-ye javvi

Fr.: extinction atmosphérique   

The decrease in the intensity of light from a celestial body due to absorption and scattering by Earth's atmosphere. It increases from the zenith to the horizon and affects short wavelengths more than long wavelengths, so that objects near the horizon appear redder than they do at the zenith.

atmospheric; → extinction.

atmospheric muon
  موءون ِ جوی، ~ هواسپهری   
muon-e javvi, ~ havâsepehri

Fr.: muon atmosphérique   

A → subatomic particle produced when → primary cosmic rays, impinge on the Earth's atmosphere producing a particle cascade, in which secondary particles decay into → muons. In the energy range up to 100 → GeV atmospheric muons come mostly from the decay of secondary → pions: π±→ μ± + anti-νμ. At higher energies, the → kaon contribution to the muon flux become significant, reaching the asymptotic value of 27% at about 10 TeV: K±→ μ± + anti-νμ.

atmospheric; → muon.

<< < -gr alp ast atm bro cor ech ext gra hyd lit mor orb pha phi pho pho pho phy roo sol sph Ste ult > >>