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: 482
Big Bang singularity
  تکینی ِ بیگ بنگ   
takini-ye Big Bang

Fr.: singularité du Big Bang   

A hypothetical state of → infinite energy density representing an infinite → gravitational field and infinite → space-time curvature. The singularity arises from using Einstein's theory of → general relativity concerning gravity. We know, however, that when the density and heat become extremely large, quantum physics of gravity becomes important. Yet Einstein's equations ignore quantum effects. In other words, in certain extreme conditions, Einstein's equations do not apply.

Big Bang; → singularity.

Big Bang theory
  نگره‌ی ِ مه بانگ، ~ بیگ بنگ   
negare-ye Meh Bâng, ~ Big Bang

Fr.: théorie du big bang   

Big Bang; → theory.

big blue bump
  قوز ِ آبی ِ بزرگ   
quz-e âbi-ye bozorg

Fr.: grande bosse bleue   

The broad continuum feature dominating the optical-ultraviolet spectra of AGNs. Most current models attribute the big blue bump to thermal emission from an optically thick accretion disk.

big; → blue; bump, → bump Cepheid.

Big Crunch
  مه رمب، رمبش ِ فرجامین   
Meh Romb, rombeš-e farjâmin

Fr.: big crunch   

The state of extremely high density and temperature into which a closed → Universe would → collapse in the distant future. If the Universe has a mass density exceeding the critical threshold, then gravity will eventually halt the expansion and cause the Big Crunch.

big; crunch "to crush, grind, or tread noisily; the act or sound of crunching," alteration of craunch, possibly of imitative origin.

Meh "large, big," → big; romb, → collapse, from rombidan "to collapse;" rombeš-e farjâmin "final collapase," from rombeš verbal noun of rombidan; farjâmin, → late.

Big Dipper
  هفت برادران، هفتورنگ، چمچه‌ی ِ بزرگ   
haft barâdarân (#), haftowrang (#), camce-ye bozorg (#)

Fr.: Grand Chariot   

A group of seven stars, an → asterism, lying inside the Northern constellation → Ursa Major. They are: → Dubhe, → Merak, → Phad, → Megrez, → Alioth, → Mizar, and → Alkaid. The group is also known as the Plough in Great Britain.

big; dipper a popular U.S. name for the asterism known in Britain as The Plough or Charles' Wain, from dip O.E. dyppan "immerse," from P.Gmc. *dupjanan.

Haft barâdarân "the seven brothers," from haft "seven" (Mid.Pers. haft, Av. hapta, cf. Skt. sapta, Gk. hepta, L. septem, P.Gmc. *sebun, Du. zeven, O.H.G. sibun, Ger. sieben, E. seven; PIE *septm) + barâdarân, plural of barâdar "brother" (Mid.Pers. brad, bardar, O.Pers./Av. brātar-, cf. Skt. bhrátar-, Gk. phrater, L. frater, P.Gmc. *brothar; PIE base *bhrater- "brother").
Haftowrang, Mid.Pers. haptôiring, from Av. haptôiringa- "with seven marks," from hapto- "seven,"as above, + iringa- "mark," cf. Skt. linga- "mark, token, sign."
Camcé "a spoon, ladle; a wooden bowl or cup;" bozorg "big, large."

big grain
  دانه‌ی ِ بزرگ   
dâne-ye bozorg

Fr.: gros grain   

A type of → interstellar dust grains with a size ranging from 150 to 1000 Å. Big grains consist of graphite and silicates. They are in → thermal equilibrium with the radiation field and their emission can be described by a modified → blackbody radiation following from → Kirchhoff's law.

big; → grain.

Big Rip
  مه‌گسست   
meh gosast

Fr.: big rip   

A cosmological hypothesis regarding the ultimate fate of the → Universe whereby in a far future galaxies and stellar systems would be torn apart due to the → accelerating expansion of the Universe depending on the kind of the → dark energy content of the Universe. According to this hypothesis, after the disruption of galaxies, stars, and planets even atoms might not be able to withstand the internal force of the expansion imposed by the dark energy.

big; M.E. rippen, origin obscure, cf. Frisian rippe "to tear, rip," M.Du. reppen, rippen "to pull, jerk," Swed. reppa, Dan. rippe "to tear, rip."

Meh "large, big," see under → big; gosast stem of gosastan "to tear, cut, break," from Mid.Pers. wisistan "to break, split," Av. saed-, sid- "to split, break," asista- "unsplit, unharmed," Skt. chid- "to split, break, cut off," PIE base *skei- "to cut, split," cf. Gk. skhizein "to split," L. scindere "to split," Goth. skaidan, O.E. sceadan "to divide, separate."

bijection
  دوشانش   
došâneš

Fr.: bijection   

A → mapping  f from a → set  A onto a set B which is both an → injection and a → surjection. More explicitly, for every element b of B there is a unique element a of A for which f(a) = b. Also known as → bijective mapping.

From bi- + → injection.

bijective
  دوشانی   
došâni

Fr.: bijectif   

Of or pertaining to a → bijection.

bi-; → injection.

bijective mapping
  همتایش ِ دوشانی   
hamtâyeš-e došâni

Fr.: application bijective   

Same as → bijection.

bijective; → mapping.

bijective morphism
  ریخت‌شناسی ِ دوشانی   
rixtšenâsi-ye došâni

Fr.: morphisme bijectif   

Same as → isomorphism.

bijective; → morphism.

bimodal
  دومد   
domod

Fr.: bimodal   

Having or providing two modes, methods, systems, etc., in particular having or occurring with two statistical modes.

bi-; → modal.

bimodal star formation
  دیسش ِ دومد ِ ستارگان   
diseš-e domod-e setâregân

Fr.: formation bimodale d'étoile   

A concept of → star formation in which → high-mass stars and → low-mass stars form in different physical conditions involving different → molecular clouds. Following the pioneering suggestion of Herbig (1962), successive investigations have generally supported the idea that star formation proceeds bimodally with respect to stellar mass. The star formation rate appears to differ both spatially and temporally for low mass and → massive stars. This is of considerable importance for galactic evolution, since the low-mass stars lock up mass and are long-lived, low luminosity survivors to the present epoch, whereas massive stars are short-lived, recycle and enrich interstellar gas, and leave dark remnants while producing a high luminosity per unit of mass (Silk, J., 1988, in Galactic and Extragalactic Star Formation, p. 503, eds. R. E. Pudritz and M. Fich).

bimodal; → star; → formation.

bimodality
  دومدی   
domodi

Fr.: bimodalité   

The quality or state of being → bimodal.

bimodal; → -ity.

bin
  ۱) باوین؛ ۲) باوینیدن   
1) bâvin; 2) bâvinidan

Fr.: 1) bin; 2) binner   

1a) General:A box or enclosed space for storing grain, coal, or the like.
1b) Electronics: In a → CCD detector, a square or rectangular group of adjacent → pixels used collectively to transport the → electron charges.
1c) In a statistical → histogram, the range of → distribution → intervals. The bin widths (or the number of bins) affect a histogram.
2) To place in a → bin; to create → binning.

M.E. binne, O.E. binn(e) "manger, crib," perhaps from O.Celt. *benna, akin to Welsh benn "a cart, especially one with a woven wicker body." The same Celtic word seems to be preserved in It. benna "dung cart," Fr. benne "a sort of box for transporting materials, especially in mines," Du. benne "large basket," from L.L. benna.

Bâvin "a basket, more precisely a small basket which contains the cotton to be spun;" bâvinidan infinitive from bâvin.

binarity
  درینی   
dorini

Fr.: binarité   

The quality or condition of being binary.

binary; → -ity.

binary
  درین، دودویی   
dorin, dodoyi (#)

Fr.: binaire   

General: Characterized by or consisting of two parts or components.
Math.: Of or relating to a system of numeration having 2 as its base.
Astro.: Physically associated pair of astronomical objects.

Binary, from L.L. binarius, from bini "two-by-two," from bis "twice, two times;" cf. Av. biš- "twice," bi- "two," Mod.Pers. do "two," PIE *dwo- "two."

Dorin, from Mid.Pers. dorin "double, pair," from do (Av. dva-, Skt. dvi-, Gk. duo, L. duo, E. two, Der. zwei, Fr. deux) "two" + rin "time, turn."
Dodoyi "two-by-two," from do, → two.

binary arithmetic
  حساب ِ درین، ~ دودو‌یی   
hesâb-e dorin, ~ dodoi (#)

Fr.: arithmétique binaire   

A system of calculation in which the only numerals used are 0 and 1. All the real numbers are represented in terms of powers of 2.

binary; → arithmetic.

binary asteroid
  سیارک ِ درین   
sayyârak-e dorin

Fr.: astéroïde binaire   

A member of a population of double objects in the main → Asteroid Belt or the → Kuiper Belt which are gravitationally bound together. So far about 200 such binary systems have been identified, while their number is increasing. 243 Ida was the first binary asteroid to be discovered during the Galileo spacecraft flyby in 1993. Other examples are → Antiope and Kalliope in the main belt and QG298 in the Kuiper Belt. The importance of these objects resides in the fact that systems with well measured orbital parameters allow the total mass to be estimated. If the sizes of the components are known then their densities can be accurately calculated. Density is an important parameter since it yields information about composition and internal structure.

binary; → asteroid.

binary black hole
  سیه‌چال ِ درین   
siyah câl-e dorin

Fr.: trou noir binaire   

A → binary system consisting of two → black holes in close orbit around each other. Same as → black hole binary.

binary; → black; → hole.

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