An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



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Number of Results: 968
asteroid belt
  کمربند ِ سیارکها   
kamarband-e sayyârakhâ

Fr.: ceinture des astéroïdes   

The region of the → solar system located between → Mars and → Jupiter where over a million objects bigger than 1 km across orbit the Sun. Another region populated by minor bodies lies beyond the orbit of → Neptune, the → Kuiper belt.

asteroid; → belt.

asteroid designation
  نامگزینی ِ سیارک   
nâmgozini-ye sayyârak

Fr.: désignation des astéroïdes   

1) For an asteroid whose orbit is precisely known, a number and optionally a proper name, e.g. (7) Iris, (24101) Cassini, (99942) Apophis.
2) For an asteroid whose orbit is not known, a provisional designation composed of four elements: number.letter.letter.(optionally)number. The first number indicates the year of discovery. The first letter denotes the half-month of the discovery (A: first half of January, Y: second half of December; the letter "I" is excluded). The second letter and the following number indicate the order of discovery within the half-month. For example, the first asteroid discovered in the first half of May 1960 is: 1960 JA. Since more than 25 objects (without "I") might be detected within a half-month, the number following the second letter indicates the number of 25 discoveries. Hence, 2001 SD3 was discovered in the second half of September 2001 and was the (D =) 4 + (25 x 3) or the 79th object found during that period.

asteroid; → designation.

asteroid family
  خانواده‌ی ِ سیارکها   
xânevâde-ye sayyârakhâ

Fr.: famille d'astéroïde   

A group of asteroids that share the same or similar proper orbital elements (semi-major axis, eccentricity, inclination). In 1918, the Japanese astronomer K. Hirayama first recognized some non random concentrations of asteroid elements. He noticed that certain "groups" of asteroids had similar orbital elements, and hence he first introduced the concept of "asteroid families," and identified three of them: Koronos, Eos, and Themis. The names of these groups were chosen by the parent (brightest) asteroid that the smaller group asteroids follow. Some of the more common asteroid families include the Trojans, which are actually not an asteroid family, but a group of asteroids caught in the Sun-Jupiter gravitational equilibrium points known as L3 and L4 → Lagrangian points.

asteroid; → family.

asteroid survey
  بردید ِ سیارکها   
bardid-e sayyarakhâ

Fr.: recherche systématique d'astéroïdes   

Systematic observation of the sky in particular searching for → asteroids that may have a close approach to the Earth. → near-Earth object.

asteroid; → survey.

Bardid, → survey; sayyârakhâ plural of sayyârak, → asteroid.

  اخترلرزه‌شناسی، اخترلرزه‌شناسیک   
axtarlarzešenâsi, axtarlarzešenâsik

Fr.: astérosismologique   

Of or relating to → asteroseismology.

spectropolarimetry; → -ic.


Fr.: astérosismologie   

The study of the → internal structure of stars through the interpretation of their pulsation periods (→ stellar pulsation). The radial pulsations are the result of → sound waves resonating in the stars interior. Different → pulsation modes penetrate to different depths inside a star. If a large number of pulsation modes occurs, then the stellar interior, which is not directly observable, can be probed from oscillation studies because the modes penetrate to various depths inside the star. Using a complex mathematical analysis, very detailed investigations of the structure of the star's interior can be carried out. Applied to the Sun, it is called → helioseismology.

From → astero- "star," from aster-, → astro-, + → seismology.

Axtarlarzešenâsi, from axtar "star," → astro-, + larzešenâsi, → seismology.

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.

  ۱) ناگراور، ۲) ناگرابین   
1) nâgerâvar, 2)nâgerâbin

Fr.: astigmate   

The optical system which is affected by → astigmatism.


  ۱) ناگراوری، ۲) ناگرابینی   
1) nâgerâvari, 2) nâgerâbini

Fr.: astigmatisme   

1) An imperfection in an optical system whereby light from a point source is formed into an image as a straight line, ellipse, or circle. The rays of light in two perpendicular planes appear as two lines at right angles.
2) A common eye defect in which the unequal curvature of one or more refractive surfaces of the eye, usually the cornea, prevents light rays from focusing clearly at one point on the retina, resulting in blurred vision.

From astigmatic, from Gk. → a- "without" + stigmatos, from stigma "a mark, spot, puncture."

1) Nâgerâvari, from nâ- "without, un" + gerâ, stem of gerâyidan "to converge," + -var, agent forming suffix, + -i, noun forming suffix.
2) The same as above with -bini "seeing, discerning".



Verbal form of → astration.



Fr.: astration   

The cyclic process in which interstellar matter is incorporated into newly formed stars, where it undergoes nuclear processing, is thus enriched with heavier elements, and then returns into the interstellar medium through supernova explosion or stellar winds to be used in the formation of a newer generation of stars.

Astration, from astrate, from astr-, → astro-, + noun-forming suffix -ation.

Setâreš, from setâridan (from setâré "star" + verb-making suffix -idan) + noun-builder -eš.

axtar- (#)

Fr.: astro-   

A combining form with the meaning "pertaining to stars or celestial bodies" used in the formation of compound words. Variants aster-, and astr- before a vowel. → star.

Gk. astron "star," akin to L. stella (Fr. étoile, from O.Fr. esteile, from V.L. *stela), Skt. str-, tara-, Av. star-, Mid.Pers. star, stârag, Mod.Pers. setâré, axtar, see below; cf. O.E. steorra, E. star, Du. ster, O.H.G. sterro, Ger. Stern, PIE *ster- "star."

Mod.Pers. axtar, → star, from Mid.Pers. axtar. The variants star-, estâr, estâré, setâré are obvious. Note also the following dialectal forms: (Lori, Laki) âsâra, (Tabari) essâra, (Laki) hasâra, (Shughni) xiterj, xtarag. The form axtar is less straightforward, leading some philologists to suggest different origins for setâré and axtar. According to W. Eilers (Iranica), axtar is a back-fomation from Mid.Pers. apâxtar "planet; north" produced by artificial dropping of the first component. Apart from phonological difficulties inherent in this suggestion, one must also explain how axtar meaning "planet" became a general designation for star, as for example in Mid.Pers. axtarmâr "astronomer," despite the relatively infinitesimal number of planets known in ancient times. W. Eilers' suggestion is pure theoretical construction; no factual evidence support it. On the other hand, in Pahlavi texts, e.g. Bundahishn, axtar is extensively used for "star, planet, and the signs of zodiac."

We suggest that both words star and axtar are etymologically related. This idea is based on the fact that "s" and "x" phonemes interchange in Persian and other IE languages. For example, the PIE *swesor "sister" has evolved into Av. xvanhar-, Mid.Pers./Mod.Pers. xâhar (Skt. svasar-, L. soror, Fr. soeur, Gk. eor "daughter, cousin, relative," Arm. k'oyr, O.H.G. swester, Ger. Schwester, Du. zuster, E. sister). Similarly, *saewel- "sun" has become Av. hvar- "sun," Mid.Pers. xavr, Mod.Pers. xor, while keeping its Av. h in Mod.Pers. hur "sun" (cf. Skt. svar-, surya-, Gk. helios, L. sol, Goth. sauil, Lith. saule). Finally, *su- "hog, pig, swine" also has changed its "s" into both "h" and "x" in Av. and Mod.Pers. hu- and xuk respectively (Skt. sukara- "boar, hog, pig," Gk. hys, L. sus, Welsh hucc, Ger. Schwein, E. swine).

  اخترباستان‌شناسی، باستان‌اخترشناسی   
axtarbâstânšenâsi(#) , bâstânaxtaršenâsi (#)

Fr.: astroarchéologie   

Same as → archaeoastronomy, megalithic astronomy.

axtarzistšenâsi (#)

Fr.: astrobiologie   

The study of life throughout the Universe, also known as exobiology.

Astrobiology, from Gk. → astro- "star" + bio "life" + -logy "science, study."

Axtarzistšenâsi, from axtar, → star, → astro- + zistšenâsi, → biology.


Fr.: astroblème   

A geological structure on the Earth's surface from an ancient meteorite impact.

Astrobleme, from → astro- + Gk. blema "scar, wound, missile," from ballein "to throw;" PIE *gwele- "to throw".

Axtarxasts, from axtar "star," → astro- + xast "wounded; scratched," from xastan "to wound, wound by scratching," Mid.Pers. xst, xs "to injure," Av. vixad- "to crush," Proto-Iranian *xad- "to wound, hurt," Skt. khad- "to hurt."

axtaršimi (#)

Fr.: astrochimie   

The study of the chemical interactions between the gas and dust of the interstellar medium.

Astrochemistry, from → astro- "star" + → chemistry.

Axtaršimi, from axtar, → astro-, + šimi, → chemistry.


Fr.: astrodynamique   

The science dealing with the motion of satellites, rockets, and spacecrafts. It uses the principles of celestial mechanics.

Astrodynamics, from → astro- "star" + → dynamics.

Axtartavânik, from axtar, → astro-, + tavânik, → dynamics.

axtarzaminšenâsi (#)

Fr.: astrogéologie   

A science concerned with the geology of solid bodies in the Solar system, such as planets, satellites, asteroids, and meteorites.

Astrogeology, from Gk. → astro- "star" + → geology.

Axtarzaminšenâsi, from axtar, → star, → + zaminšenâsi, → geology.

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.

ostorlâb (#)

Fr.: astrolabe   

An ancient instrument for solving problems relating to time and the position of the Sun and stars in the sky. It had many uses, including telling time during the day or night, finding the time of sunrise and sunset and, thus, the length of the day, and locating celestial objects in the sky. It was widely used until replaced by the → sextant. The → planispheric astrolabe, which is the most common type of the instrument, is typically made up of a graduated disk hanging vertically, which is rotated so that it can be directed to the star chosen. The local time can thus be read from the face of the astrolabe, and different tables, at various latitudes, can be used. More specifically, a planispheric astrolabe is made up of the following main components: → mater, → tympanum, → rete, → alidade, → throne, → limb, → pin, → horse, → front, and → back. The astrolabe was invented by Greeks, and some historians have attributed it to Hipparchus (c190-c120 BC). Modern, sophisticated versions (such as → prismatic astrolabe and → Danjon astrolabe), are used for high precision measurements of star positions. See also → particular astrolabe, → spherical astrolabe, and → universal astrolabe.

M.E., from O.Fr. astrelabe, from M.L. astrolabium, from Gk. astrolabos (organon) "star taking (instrument)," from astron "star," → astro- + lambanein "to take."

Ostorlâb, from Ar. usturlab, from Gk. astrolabos, as above.

<< < -ab ab- abo abs abs acc acc ack act acu add adi adv aff agg Ald Alf ali Alm alp alt amb an- ana ang ang ann ano ant ant ape apo app app arc Arg ari art ass ast ast ast Atl ato ato aub aut Avo axi > >>