An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



<< < -ti tan Tay tem ten Ter the the the the thi thr tid tim Tit top tot tra tra tra tra tri Tri tru Tuc tur Tyc Typ > >>

Number of Results: 544
true celestial pole
  قطب ِ آسمانی ِ راستین   
qotb-e âsmâni-ye râstin

Fr.: pôle céleste vrai   

The direction of the Earth's instantaneous rotation pole. It differs from the pole due to the short time-scale (days or decades) variations called → nutation.

true; → celestial; → pole.

true equator
  هموگار ِ راستین   
hamugâr-e râstin

Fr.: équateur vrai   

Same as → true celestial equator.

true; → equtor.

true equinox
  هموگان ِ راستین   
hamugân-e râstin

Fr.: équinoxe vrai   

The intersection of the → ecliptic with the → true celestial equator for a given epoch. It is derived from the → mean equinox accounting for the → nutation.

true; → equinox.

true horizon
  افق ِ راستین   
ofoq-e râstin

Fr.: horizon vrai   

A large circle of the → celestial sphere whose plane is perpendicular to the radius of the Earth through the point. Same as → astronomical horizon. The → visible horizon usually lies lower than the true horizon. See also → dip of the horizon.

true; → horizon.

true north
  هودر ِ راستین   
hudar-e râstin

Fr.: nord vrai   

The geographic north defined by the rotational pole of the Earth, as opposed to magnetic north defined by the geomagnetic north pole.

true; → north.

true position
  نهش ِ راستین   
neheš-e râstin

Fr.: position vraie   

The coordinates of an object for a given date, with respect to the true equator and the true equinoxes for the instant of time in question.

true; → position.

true sidereal time
  زمان ِ اختری ِ راستین   
zamân-e axtari-ye râstin

Fr.: temps sidéral vrai   

The → sidereal time with respect to the → true equinox.

true; → sidereal; → time.

true Sun
  خورشید ِ راستین   
xoršid-e râstin

Fr.: Soleil vrai   

The Sun as seen in the sky, also referred to as the → apparent Sun; in opposition to → mean Sun.

true; → Sun.

Trumpler 14
  ترامپلر ۱۴   
Trumpler 14

Fr.: Trumpler 14   

A young → massive star cluster in the → Carina Nebula, lying about 10 arcmin to the north-west of → Trumpler 16. It comprises several → O-type stars. In particular, its core contains at least three very early O-type stars; → HD 93129.

From a catalog by Robert J. Trumpler (1886-1956), the Swiss-American astronomer who studied the → open clusters at Lick Observatory (1930). He was the first to produce a definite evidence of the existence of → interstellar reddening, due to → absorption, and to estimate its magnitude.

Trumpler 16
  ترامپلر ۱۶   
Trumpler 16

Fr.: Trumpler 16   

A → massive star, and the most populous cluster of the → Carina Nebula. It contains several → O-type stars and three known → Wolf-Rayet stars in addition to the famous → LBV star → Eta Carinae. Trumpler 16 is probably older than → Trumpler 14.

Trumpler 14.

  کل کردن   
kol kardan

Fr.: tronquer   

To shorten by cutting off a part.
Math.: 1) To shorten a number by dropping a digit or digits; e.g. to shorten 3.438 to 3.4.
2) To remove portions of solids falling outside a set of symmetrically placed planes.

From L. truncatus "cut off," p.p. of truncare "to maim, cut off," from truncus "mutilated, cut off."

Kol kardan "to cut off the end of; to dock a tail," from kol "docked, short," variants in a large number of dialects: kola, kalta, kel, kelma, koc, kall, kor, kul in Gilaki, Tâleši, Lori, Malâyeri, Hamedâni, Qâeni, and others, cf. Av. kaurvô- "bald, docked," kaurvôduma- "with a bald tail," kaurvôgaoša- "with bald ears;" cf. Gk. kol(os) "docked" (kolouros "dock-tailed;" L. colurus) + kardan "to do, to make" (Mid.Pers. kardan, O.Pers./Av. kar- "to do, make, build," Av. kərənaoiti "makes," cf. Skt. kr- "to do, to make," krnoti "makes," karma "act, deed;" PIE base kwer- "to do, to make").

  کل‌کرد، کل‌شد   
kolkard, kolšod

Fr.: troncature   

The act or process of truncating, as → disk truncation.

Verbal noun from → truncate.

râstini (#)

Fr.: vérité   

1) The quality of being true, genuine, actual, or factual.
2) Something that is → true as opposed to → false.
3) Logic: The correct corresponding of a → proposition with a → fact. See also → truth value, → partial truth.

M.E. treuthe; O.E. trêowth "faith, faithfulness, fidelity; quality of being true," from triewe, treowe "faithful," → tue, with suffix *-itho-th.

Noun from râstin, → true, + noun suffix -i.

truth function
  کریای ِ راستینی   
karyâ-ye râstini

Fr.: fonction de vérité   

A → total function from → truth values to truth values (a sequence of truth values).

truth; → function.

truth table
  جدول ِ راستینی   
jadval-e râstini

Fr.: table de vérité   

A table with columns and rows that lists the resultant → truth value of the given → sentences for each of the possible combinations of truth values to the simple sentences out of which the given sentences are constructed.

truth; → value.

truth value
  ارزش ِ راستینی   
arzeš-e râstini

Fr.: valeur de vérité   

The quality of a logical → proposition (or a formal → symbol) which describes the relation of a proposition to → truth. The traditional → formal logic admits only two contradictory values, → true or → false. In → symbolic logic, more specifically in → polyvalent logics, other truth values are used (such as possible, impossible, undetermined, probable, random, etc.).

truth; → value.

tsunami (#)

Fr.: tsunami   

A huge wave, caused by undersea earthquakes, volcanic eruptions, or, more rarely, by asteroid or meteoroid impact (as in the case of the K-T extinction).

From Japanese tsunami, from tsu "harbor" + nami "waves."

lulé (#)

Fr.: tube   

1) A long hollow cylinder of metal, glass, rubber, or other material used to transport or contain liquids or gases.
2) An electronic device in which electrons operate in a gas or in vacuo inside a closed envelope.

M.E., from M.Fr. tube, from L. tubus "tube, pipe," of unknown origin.

Lulé "tube, pipe; roll," dialectal Lori, Laki lil, Laki lul "wanderer;" Hamadâni lul "spiral, coil."

tube of flow
  لوله‌ی ِ تچان   
lule-ye tacân

Fr.: tube d'écoulement   

Same as → flow tube.

tube; → tube.

tube of flux
  لوله‌ی ِ شار   
lule-ye šâr

Fr.: tube de flux   

Bundles of lines of electrical intensity into which the vector field of electrical force can be divided. Same as tube of force, field tube.

tube; → flux.

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