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: 1295
spontaneous emission
  گسیل ِ سرخود   
gosil-e sarxod

Fr.: émission spontanée   

The emission of electromagnetic radiation from an atom or molecule that does not depend on the presence of external fields.

spontaneous; → emission.

spontaneous symmetry breaking
  شکست ِ سرخود ِ همامونی   
šekast-e sarxod-e hamâmuni

Fr.: brisure spontanée de symétrie   

A physical phenomenon whereby a symmetric system becomes permanently asymmetric. A simple example is a ball lying on top of a hill in equilibrium. The hill-ball system is symmetric about the vertical axis through the top of the hill. Moreover, there is no preferred horizontal direction to the system. However, its state is unstable, since the slightest perturbing force will cause the ball to roll down the hill in some particular direction. The system becomes permanently asymmetric because the ball will not roll uphill by itself. Symmetry breaking is found in several fields of physics, for example in → magnetism (→ ferromagnetism), → thermodynamics (→ crystallization), and → particle physics, where it constitutes the basis of → electroweak interactions. In cosmology, according to the → Big Bang model, the fundamental forces of the Universe split off from one another in a form of spontaneous symmetry braking. If a single, unified force existed with a certain symmetry just after the Big Bang, if that symmetry were somehow broken so that the unified force were fractured, then the result might be several fundamental forces. See also → grand unified theory, → theory of everything, → phase transition.

spontaneous; → symmetry; → break.

sporadic meteor
  شهاب ِ گهگاهی   
šahâb-e gahgâhi

Fr.: météore sporadique   

A meteor occurring occasionally, and not associated with any known meteor shower.

Sporadic, from M.L. sporadicus "scattered," from Gk. sporadikos "scattered," from sporas (genitive sporados) "scattered," from spora "seed, a sowing;" related to sporos "sowing," and speirein "to sow," from PIE *sper- "to strew;" → meteor.

Šahâb, → meteor; gahgâhi "from time to time," from gah, gâh "time; place" (Mid.Pers. gâh, gâs "time;" O.Pers. gāθu-; Av. gātav-, gātu- "place, throne, spot;" cf. Skt. gâtu- "going, motion; free space for moving; place of abode;" PIE *gwem- "to go, come").

Sporer minimum
  کمینه‌ی ِ اشپورر   
kamine-ye Spörer

Fr.: minimum de Spörer   

A period of low → solar activity that lasted from about A.D. 1420 to 1570. It occurred before → sunspots had been studied, and was discovered by analysis of the proportion of carbon-14 in tree rings, which is strongly correlated with solar activity.

Named for the German astronomer Gustav Spörer (1822-1895); → minimum.

Sporer's law
  قانون ِ اشپورر   
qânun-e Spörer

Fr.: loi de Spörer   

The empirical law that predicts the variation of → sunspot latitudes during a → solar cycle. At the start of a sunspot cycle, sunspots tend to appear around 30° to 45° latitude on the Sun's surface. As the cycle progresses, they appear at lower and lower latitudes, until 5° to 10°, at the end of the cycle. This tendency is revealed on a → butterfly diagram. Although named after Gustav Spörer, the "law" was first discovered by Richard Carrington.

Sporer minimum; → law.

spot
  لک، لکه   
lak (#), laké (#)

Fr.: tache   

M.E. spotte "a spot, blot, patch;" M.Du. spotte "spot, speck."

Lak(k), lak(k)é "spot, stain."

spring
  ۱) بهار؛ ۲) چشمه؛ ۳) فنر   
1) bahâr (#); 2) cešmé (#); 3) fanar (#)

Fr.: 1) printemps; 2) source; 3) ressort   

1) The season that starts when the Sun, during its apparent yearly motion, attains the celestial longitude 0 degree in the Northern Hemisphere and 180 degrees in the Southern Hemisphere. The current length of the spring season, around the year 2000, is about: spring 92.76 days.
2) A surface flow of groundwater which occurs any time the water table intersects the surface. Related concept → source = xan (خن).
3) An elastic device, usually a twisted piece of metal, that returns to its original shape when it is pressed or stretched, used chiefly to exert constant tension or absorb movement.

1) From the verb M.E. springen; O.E. springan "to leap, burst forth, fly up;" the notion is of the "spring of the year," when plants "spring up" cf. Du., Ger. springen.
2) Similarly from the verb, as above, M.E. spring(e); O.E. spring, spryng; cf. O.H.G., Dan., Sw. spring.
3) From the verb spring, as above.

1) Bahâr, from Mid.Pers. wahâr "spring;" O.Pers. vāhara- "spring time," θūra-vāhara- "name of a spring month;" Av. vaηhar "spring;" cf. Skt. vasara- "relating or appearing in the morning;" Gk. ear "spring;" L. uēr "spring," vernus "of spring;" O.N. vār "spring;" Lith. vasara "summer;" O.C.S. vesna "spring."
2) Cešmé "spring, source," from Mid.Pers. cašmag "spring, source," supposed to be related to cašm, cešmeye.
3) Fanar, from Turk fanâr.

spring constant
  پایای ِ فنر   
pâpâ-ye fanar

Fr.: constante de rappel du ressort   

A characteristic of a spring which is defined as the ratio of the force affecting the spring to the displacement caused by the force. In other words, the spring constant is the force applied if the displacement in the spring is unity. It is expressed by the equation k = -F/x (from → Hooke's law), where F = force applied, x = displacement by the spring. The spring constant is usually expressed in Newton per meter (N/m).

spring; → force.

spring tide
  مهکشند   
mehkešand (#)

Fr.: grande marée   

Tide that occurs when the → Earth, the → Sun, and the → Moon are in a line. This happens approximately twice a month, around → new moon and → full moon. In such a condition, known as → syzygy, the tidal force due to the Sun reinforces that due to the Moon. Spring tides have nothing to do with the season spring. The name derives from the meaning "a leap, jump, bound, rise."

Spring "a leap, jump, or bound;" M.E. springen, from spring O.E. springan "to leap, fly up; spread, grow;" cognates: O.N., O.Fris. springa, M.Du. springhen, O.H.G. springan, Ger. springen, from PIE *sprengh-, form *spergh- "to move, hasten, spring" (Skt. sprhayati "desires eagerly," Gk. sperkhesthai "to hurry."

Mehkešandak "high tide," from meh-, → high, + kešand, → tide.

sprinkle
  ۱) پشکیدن، پشکاندن؛ ۲) پشکه   
1) peškidan, peškândan; 2) pešké

Fr.: 1) asperger; 2) aspersion   

1) To scatter (a liquid, powder, etc.) in drops or particles.
2) The act or an instance of sprinkling.

M.E. sprenklen (v.); cognate with Du. sprenkelen, Ger. sprenkeln; O.E. sprengan "to sprinkle, make (something) spring, scatter."

Peškidan, from (Malâyeri, Hamedâni) peška "sprinkle, water drop," variant of (Dehxodâ) pašang "sprinkle," pešanjidan "to sprinkle, spray;" (dialects of Khorâsân, Bandar Abbâs, Kermân, Dari Kermân, Lâ) pešang "spraying;" ultimately from Proto-Ir. *pati-haic- from *haic- "to pour (out), moisten);" cf. Av. patihaēc- "to sprinkle all over, pour on;" Mid.Pers. pšnc-/paššinj- "to sprinkle;" related to Pers. xēs, xis, hēs "wet;" O.H.G. sīhan "to sift;" O.E. sēon "to flow away, to sift;" PIE root *seikw- "to pour" (Cheung 2007).

sprite
  فرفده   
farfadé

Fr.: farfadet   

A very brief, predominantly red, luminous glow, that occurs in the → mesosphere. Sprites occur high above large → thunderstorms and last only a few milliseconds. They have a lump of light on top and numerous tendrils descending downward. Sprites can shoot about 90 to 95 km up into the atmosphere, reaching the → ionosphere, and extend 160 km across. They are very difficult to see, and for that reason were not reliably recorded until 1989. See also → elve; → blue jet.

Sprite "elf, fairy, eerie, ghost-like quality," so named by D. Sentman et al. (1995, Geophys. Res. Let, 22, 1205) because of the fleeting nature of sprites; M.E., from O.Fr. esprit "spirit," from L. spiritus "soul, vigor, breath," related to spirare "to breathe."

Farfadé, from Fr. farfadet, of dialectal origin, derived from fado "fairy."

spur
  ۱، ۲، ۳، ۴، ۵) شخاک، ۱) مهمیز   
1, 2, 3, 4, 5) šaxâk, 1) mehmiz

Fr.: éperon   

1) A pointed device on the heel of a rider's boot used to urge on the horse.
2) A sharp horny part on the leg of some birds.
3) Geology: A lateral lower mountain ridge descending from the mountain or the main ridge crest.
4) Mining: A small vein branching from a main one.
5) → Orion Spur.

M.E. spur, from O.E. spura, spora "metal implement worn on the heel to goad a horse," akin to M.Du. spore, Du. spoor, O.H.G. sporo, Ger. Sporn "spur."

Šaxâk, from šax "hard ground, especially on the summit or at the skirt of a mountain; anything hard; a mountain," + noun/nuance suffix -âk.
Mehmiz "a spur, a goad," loan from Ar.

sputter
  اُسپراندن   
osparândan

Fr.:   

To emit particles, sparks, etc., forcibly or explosively, especially accompanied by sputtering sounds.

Originally "to spit with explosive sounds," cognate with Du. sputteren, W.Fris. sputterje.

Osparândan, literally "to throw out," from os- "out," → ex-, + parândan "to eject," transitive verb of paridan "to fly" (from Mid./Mod.Pers. par(r) "feather, wing," Av. parəna- "feather, wing;" cp. Skt. parna "feather," E. fern; PIE *porno- "feather").

sputtering
  اُسپرانی   
osparâni

Fr.: éjection par collision ionique   

The ejection of charged particles or atoms by a solid or liquid surface which undergoes collision with high-energy ions.

Verbal noun of → sputter.

squall
  بادزد   
bâdzad (#)

Fr.: rafale   

A sudden, violent gust of wind, often accompanied by rain, snow, or sleet. A sudden increase of the mean wind speed which lasts for several minutes at least before the mean wind returns to near its previous value. It is often accompanied by rain or snow.

Probably from a Scand. source (cf. Norw. skval "sudden rush of water," Sw. skvala "to gush, pour down").

Bâdzad, from bâd, → wind + zad past stem of zadan "to strike, beat; to do; to play an instrument" (Mid.Pers. zatan, žatan; O.Pers./Av. jan-, gan- "to strike, hit, smite, kill" (jantar- "smiter"); cf. Skt. han- "to strike, beat" (hantar- "smiter, killer"); Gk. theinein "to strike;" L. fendere "to strike, push;" Gmc. *gundjo "war, battle;" PIE *gwhen- "to strike, kill").

square
  چاروش، چهارگوش   
câruš, cahârguš

Fr.: carré   

1) A rectangle having all four sides of equal length.
2) The second power of a quantity, expressed as a2 = a × a, where a is the quantity. → inverse square law.

M.E., from O.Fr. esquire "a square, squareness," from V.L. *exquadra, from *exquadrare "to square," from L. → ex- "out" + quadrare "make square," from quadrus "a square," from quattuorfour.

Câruš, from Av. caθruša- "four sides (of a four-sided figure)", from caθru- "four," Mod.Pers. cahâr, câr "four" + uša- "angle," Mod.Pers. guš, gušé.

square degree
  درجه‌ی ِ چاروش   
daraje-ye câruš

Fr.: degré carré   

A solid angle whose cone is a tetrahedral pyramid with an angle between its edges equal to 1°. 1 square degree = 3.046 x 10-4 sr = 2.424 x 10-5 solid angle of a complete sphere.

square; → degree.

Square Kilometer Array (SKA)
     
SKA

Fr.: SKA   

An international project to construct a highly sensitive radio interferometer array operating between 0.15 and 20 GHz with an effective collecting area of one square kilometer. The number of individual telescopes will be 2000 to 3000. SKA will have a sensitivity 100 times higher than that of today's best radio telescopes and an angular resolution < 0.1 arcsec at 1.4 GHz. The site will be selected in 2012 and early science with Phase 1 is scheduled for from 2016 on. See also the SKA homepage.

square; → kilometer; → array.

square matrix
  ماتریس ِ چاروش   
matris-e câruš

Fr.: matrice carée   

A → matrix with equal numbers of → rows and → columns (i.e., an n × n matrix).

square; → matrix.

Square of Pegasus
  چهارگوش ِ پگاسوس   
Chahârguš-e Pegasus

Fr.: Carrée de Pégase   

A large → asterism of four stars, approximately square in shape, in the northern sky. Three of the stars, → Markab, → Scheat, and → Algenib, belong to the constellation → Pegasus. The fourth, → Alpheratz, was lost to Pegasus when the constellation boundaries were formalised, and now lies just within the borders of → Andromeda.

square; → Pegasus.

Chahârguš, → tetragon; → Pegasus.

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