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: 888
aperture synthesis
  هندایش ِ دهانه   
handâyeš-e dahâné

Fr.: synthèse d'ouverture   

The method of combining the signals received by several smaller telescopes distributed over a very large area or baseline to provide the high angular resolution of a much large telescope.

aperture; → synthesis.

apex
  چکاد   
cakâd (#)

Fr.: apex   

1) General: The highest point or level.
2) Mathematics: The highest point of a geometric figure or solid relative to some line or plane.
3) Astro.: Solar apex. The point on the celestial sphere toward which the Sun and the solar system are moving relative to the stars in our vicinity.

L. apex "summit, peak, tip," probably related to apere "to fasten, fix," hence "the tip of anything".

Cakâd "summit of a mountain; top, crown of the head, top of the forehead," from Mid.Pers. cakât "summit," cf. Skt. kakud-, kakuda- "peak, summit," L. cacumen "top, point," cumulus "heap."

aphelion
  اپاهور   
apâhur

Fr.: aphélie   

The point in the orbit of a planet, or other object in the solar system, which is furthest from the Sun.

Aphelion, from L. aphelium, from Gk. → apo- + helios "sun," cognate with L. sol, Skt. surya, Av. hvar-, Mod.Pers. xor, hur, O.H.G. sunna, Ger. Sonne, E. sun; PIE *sawel- "sun".

Apâhur, from Pers. prefix apâ, → apo-, + hur "sun."

aphelion distance
  اپست ِ اپاهوری   
apest-e apâhuri

Fr.: distance à l'aphélie   

The distance between the → Sun and an → object in orbit around it when they are at their farthest approach.

perihelion; → distance.

aplanatic lens
  عدسی ِ نابیراه   
adasi-ye nâbirah

Fr.: lentille aplanétique   

A lens designed so as to minimize both its → spherical aberration and → coma.

aplanatism; → lens.

aplanatic system
  راژمان ِ نابیراه   
râžmân-e nâbirah

Fr.: système aplanétique   

An → optical system that is able to produce an image essentially free from → spherical aberration and → coma. See also the → Abbe sine condition.

aplanatism; → system.

aplanatism
  نابیراهی   
nâbirahi

Fr.: aplanétisme   

Freedom from spherical aberration and coma.

Aplanatism, from aplanatic, from a- "negation prefix" + Gk. plane "wandering," from planasthai "to wander" + -tic adjective-forming suffix.

Nâbirahi, from nâ- "negation prefix" + birah "a devious path; a wanderer, who deviates, errs," + -i noun affix.

apo-
  اپا-   
apâ-

Fr.: apo-   

Prefix meaning "away from, off; out of; without," ap- before a vowel or h.

From Gk. apo "away from, from;" cf. Av. apâ "away from, from."

Persian apâ- from Av. and O.Pers. apâ "away from, from". Compare with Skt. apa "away, off," L. ab- "from, away," Hittite appa, Gothic af-, Ger. ab-, E. of, off; PIE *apo- "off, away."

apoapsis
  اپاهباک   
apâhabâk

Fr.: apoapse   

The point in an orbit where the moving body lies furthest from the celestial body around which it turns.

Apoapsis, from → apo- + → apsis.

Apâhabâk, from apâ-, → apo-, + habâk, → apsis.

apocenter
  اپامرکز   
apâmarkaz

Fr.: apocentre   

The point on an elliptic orbit at the greatest distance from the principal focus or center of attraction.

Apocenter, from → apo- + → center.

Apâmarkaz, apâkayân, from apâ-, → apo-, + markaz or kayân, → center.

apochromat
  عدسی ِ اپافام   
adasi-ye apâfâm

Fr.: apochromatique   

Same as → apochromatic lens.

apochromatic
  اپافام   
apâfâm

Fr.: apochromatique   

Corrected for → spherical aberration at two wavelengths or colors and for → chromatic aberration at three wavelengths.

apo-; → chromatic.

apochromatic lens
  عدسی ِ اپافام   
adasi-ye apâfâm

Fr.: lentille apochromatique   

A lens that is → apochromatic.

apochromatic; → lens.

apochromatic system
  راژمان ِ اپافام   
râžmân-e apâfâm

Fr.: système apochromatique   

An optical system that is → apochromatic.

apochromatic; → system.

apochromatism
  اپافامی   
apâfâmi

Fr.: apochromatisme   

The capacity of an optical system to bring three widely separated wavelengths of light into a single focus.

apochromatic; → -ism.

apochromatize
  اپافامیدن، اپافام کردن   
apâfâmidan, apâfâm kardan

Fr.: apochromatiser   

To bring the wavelengths of the spatially separate colors to a common focus.

apochromat; → -ize.

apocynthion
  اپامه، اپاماه   
apâmah, apâmâh

Fr.: apolune   

The point in a lunar orbit that is farthest from the center of the Lune. Also apolune.

Apocynthion, from → apo- "away from, off" + cynthion, from Gk. Cynthia "goddess of the Moon."

Apâmah, apâmâh, from apâ, → apo-, + mah, mâh, → Moon.

apodization
  پازدایی   
pâzodâyi

Fr.: apodisation   

1) Generally, any process suppressing the secondary maxima of a diffraction pattern, such as the faint rings around the Airy disk of an optical image. This allows the telescope to resolve finer details.
2) Over a telescope aperture, the use of a screen that progressively cuts down, from the center to the edge of the aperture, the amount of light transmitted, in order to reduce diffraction.
3) A mathematical treatment carried out on data received from an interferometer before the Fourier transformation is calculated to obtain the spectrum.

Apodization from v. apodize, → a- "negation prefix" + pod from Gk. podos "foot" (compare with Pers. , see below) + -tion "noun forming suffix;" literally "removing feet," i.e. suppressing the secondary maxima at the side of the Airy spot.

Pâzodâyi "removing feet," from "foot," Mid.Pers. pâd, pây , Av. pad-, Skt. pat, Gk. pos, gen. podos, L. pes, gen. pedis, PIE *pod-/*ped-. Zodâyi, n. from zodudan "to polish, clean," Mid.Pers. uzdâtan, Av. uzdâ-, from uz-, → ex-, + dâ- "make, create."

apofocus
  اپاکانون   
apâkânun

Fr.: apocentre   

The point on an elliptic orbit at the greatest distance from the principal focus. Also knwon as → apocenter.

From → apo- "away from, off," + → focus.

From apâ-, → apo-, + kânunfocus.

apogalactic
  اپاکهکشانی   
apâkahkašâni

Fr.: apogalactique   

Of or pertaining to an → apogalacticon.

apo-; → galactic.

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