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

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 46 Search : gas
gaseous nebula
  میغ ِ گازی   
miq-e gâzi

Fr.: nébuleuse gazeuse   

An → H II region, a → planetary nebula, or a → supernova remnant.

gaseous; → nebula.

greenhouse gases
  گاز‌های ِ دارای ِ اُسکر ِ گرمخانه   
gâzhâ-ye dârâ-ye oskar-e garmxâné

Fr.: gaz à effet de serre   

Gases responsible for the greenhouse effect. These gases include: water vapor (H2O), carbon dioxide (CO2); methane (CH4); nitrous oxide (N2O); chlorofluorocarbons (CFxClx); and tropospheric ozone (O3).

greenhouse; → gas.

Greenwich Apparent Sidereal Time (GAST)
  زمان ِ اختری ِ پدیدار ِ گرینویچ   
zamân-e axtari-ye padidâr-e Greenwich

Fr.: temps sidéral apparent de Greenwich   

The → Greenwich Mean Sidereal Time corrected for → nutation. Therefore, it is measured with respect to the → true vernal equinox. GAST and GMST differ by the → equation of the equinoxes.

Greenwich Meridian; → apparent; → sidereal; → time.

ideal gas
  گاز ِ آرمانی، ~ ِ مینه‌وار   
gâz-e ârmâni, ~-e minevâr

Fr.: gaz idéal   

Theoretical gas assumed to consist of perfectly elastic molecules of negligible volume and mutual attraction force. Also called → perfect gas.

ideal; → gas.

ideal gas law
  قانون ِ گاز ِ آرمانی، ~ ~ مینه‌وار   
qânun-e gâz-e ârmâni, ~ ~ minevâr

Fr.: loi des gaz parfaits   

An → equation of state that relates pressure (P), temperature (T), and volume (V) of an ideal or → perfect gas: PV = nRT, where n is the number of → moles of gas present and R is the → universal gas constant. Equivalently: PV = NkT, where N is the number of atoms of gas present and k is → Boltzmann's constant.

ideal; → gas; → law.

inert gas
  گاز ِ لَخت   
gâz-e laxt

Fr.: gaz rare, ~ inerte   

Any one of six gases helium, neon, argon, krypton, xenon, and radon, all of whose atomic shells contain complete numbers of electrons so that the atoms are almost completely chemically inactive. Same as noble gases.

inert; → gas.

interplanetary gas
  گاز ِ اندرسیاره‌ای   
gâz-e andarsayyâreyi

Fr.: gaz interplanétaire   

Electrically charged particles of the solar wind and gas liberated from comets within the solar system.

interplanetary; → gas.

interstellar gas
  گاز ِ اندر-اختری   
gâz-e andaraxtari

Fr.: gaz interstellaire   

Gas, mostly hydrogen, in the interstellar space found in a variety of forms: molecular, atomic, ionized, plasma.

interstellar; → gas.

ionized gas
  گاز ِ یونیده   
gâz-e yonidé (#)

Fr.: gaz ionisé   

A gas composed partially or totally of → ions.

ionized; → gas.

kinetic theory of gases
  نگره‌ی ِ جنبشی ِ گاز‌ها   
negare-ye jonbeši-ye gâzhâ (#)

Fr.: théorie cinétique des gaz   

A theory that explains macroscopic properties of gases, such as pressure, temperature, or volume, by considering their molecular composition and motion.

kinetic; → theory; → gas.

Markab (α Pegasi)
  مرکب   
Markab

Fr.: Markab   

A blue star of visual magnitude 2.49, the brightest in the constellation → Pegasus. Markab is a relatively hot star of → spectral type B9, with a total luminosity about 200 times that of the Sun, a surface temperature of about 11,000 K, and a radius 4.3 times solar lying 140 light-years away.

Markab seems to be a corruption of Mankab in the original Ar. name of this star Mankib al-faras (منکب‌الفرس) "the horse's shoulder," from mankib "shoulder" + faras "horse," referring to Pegasus in Gk. mythology.

megastructure
  مگاساختار   
megâsâxtâr

Fr.: mégastructure   

Same as → Dyson sphere.

mega-; → structure.

neutral gas
  گاز ِ نتار   
gâz-e natâr

Fr.: gaz neutre   

A gas which is not ionized.

neutral; → gas.

noble gas
  گاز ِ هوپد   
gâz-e huped

Fr.: gaz rare   

A gaseous chemical element that does not readily enter into chemical combination with other elements. Examples are helium, argon, krypton, xenon, and radon. Same as → inert gas.

Noble, from O.Fr. noble, from L. nobilis "well-known, famous, of superior birth," earlier gnobilis, literally "knowable," from gnoscere "to come to know" (Fr. connaître; Sp. conocer); cognate with Pers. šenâxtan "to know, discern, distinguish, be acquainted with;" Mid.Pers. šnâxtan, šnâs- "to know, recognize," dânistan "to know;" O.Pers./Av. xšnā- "to know, learn, come to know, recognize;" cf. Skt. jñā- "to recognize, know," jānāti "he knows;" Gk. gignoskein "to know, think, judge;" P.Gmc. *knoeanan; O.E. cnawan; E. know; Rus. znat "to know;" PIE base *gno- "to know;" → gas.

Gâz, → gas; huped "noble," from Mid.Pers. hupid "noble," from hu- "good, well" (Mid.Pers. hu-; O.Pers. hu- "good, well" (ukāra- "having good people"); Av. hu-, hū- "well, good, beautiful" (hu-kərp- "well-shapen," hūxta- "well spoken," hu-manah- "good-minded"); cf. Skt. su- "good" (svasti "well-being, good luck," sumánas- "good-minded," sūktá- "well spoken"); L. from Gk. eu "well," combining form of eus "good" (hu-gies "healthy"); Gallic su-; O.S. su-; Welsh hy-; PIE base *su-) + pid "father," variant of pidar; Mod.Pers. pedar "father" (O.Pers. pitā- "father;" Av. patar-; Skt. pitár-; Gk. pater; L. pater, O.H.G. fater).

outgassing
  ا ُسگازش   
osgâzeš

Fr.: dégazage   

1) General: The slow release of a gas that was trapped, frozen, absorbed or adsorbed in some material.
2) Planets: Release of the gases locked in the interior of a planet during volcanic activity so that they become part of the planet's atmosphere.

out + verbal noun from → gas.

Pegasus
  پگاسوس، اسب ِ بالدار   
Pegâsus (#), asb-e bâldâr (#)

Fr.: Pégase   

The Winged Horse. A large constellation in the northern hemisphere at 22h 50m right ascension, 20° north declination. The stars → Markab, → Scheat, and → Algenib form three corners of the famous Great → Square of Pegasus, which is completed by the star → Alpheratz from neighboring → Andromeda. Abbreviation: Peg; Genitive: Pegasi.

In Gk. mythology, Pegasus is the winged horse that was fathered by Poseidon with Medusa. When the head of Medusa was cut off by Perseus, the horse sprang forth from her pregnant body. Pegasus aided Perseus in his fight against both the Chimera and the Amazons.

Pegâsus, from Gk., as above; asb-e bâldâr "Winged Horse," referring to the Gk. mythology, from asbhorse; bâl, → wing; dâr "having, possessor" (from dâštan "to have, to possess," Mid.Pers. dâštan, O.Pers./Av. root dar- "to hold, keep back, maintain, keep in mind," Skt. dhr-, dharma- "law," Gk. thronos "elevated seat, throne," L. firmus "firm, stable," Lith. daryti "to make," PIE *dher- "to hold, support").

perfect gas
  گاز ِ فرساخت   
gâz-e farsâxt

Fr.: gaz parfait   

A hypothetical gas with molecules of negligible size that exert no intermolecular forces. Also called → ideal gas.

perfect; → gas.

permanent gas
  گاز ِ ماندگار   
gâz-e mândegâr

Fr.: gaz permanent   

Gas which cannot be liquefied by pressure alone; gas above its critical temperature.

permanent; → gas.

photon gas
  گاز ِ فوتونی   
gâz-e fotoni

Fr.: gaz de photons   

Electromagnetic radiation in equilibrium in a → black body cavity. Photons can be treated as the simplest → ideal gas because all the particles move at the same velocity, the → speed of light. There are, nevertheless, two main differences. 1) Photons are → bosons and → Bose-Einstein statistics must be used. However, photons do not interact with each others so that no approximation is made by neglecting inter-particle forces. 2) Some photons scatter off the walls, with some being absorbed and new ones being emitted continually; so that no constraint can be placed on their number.

photon; → gas.

polytropic gas
  گاز ِ بُلگشتی   
gâz-e bolgašti

Fr.: gaz polytropique   

A gas capable of undergoing a → polytropic process.

polytropic; → gas.

<< < 951 gas rar > >>