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: 486
burst of star formation
     
belk-e diseš-e setâregân

Fr.: flambée de formation d'étoiles   

An intense → star formation activity in a region of → interstellar medium or, more globally, in a → galaxy. It is characterized by a → star formation rate which is much higher than the corresponding average. Same as → starburst.

burst; → star; → formation.

burster
  بلکور   
belkvar

Fr.: source à sursaut   

A → source that shows sudden intense → emission of → X-rays or → gamma rays with a rapid rise and decay. Often it cannot be identified with any → optical counterpart.

From → burst + -er a noun-forming suffix.

Belkvar, from belk, → burst, + agent noun suffix -var.

butterfly diagram
  نمودار ِ پروانه‌وار   
nemudâr-e parvânevâr

Fr.: diagramme en papillon   

A graph on which the latitudes of → sunspots are plotted against time. It shows how sunspots migrate from high latitudes (30°- 40° north or south) to the solar equator (latitude of about 5°) during each → solar cycle, according to → Sporer's law. The shape of these distributions, when represented for both hemispheres, resembles the wings of a butterfly. The diagram was first created by Edward W. Maunder in 1904 to illustrate the solar cycle (M.S.: SDE).

Butterfly, from M.E. butterflye, from O.E. butorfleoge, from butor, butere "butter" floge "fly," but the etymology is not clear; → diagram.

Nemudâr, → diagram; parvânevâr "resembling a butterfly," from parvâné "butterfly" + -vâr similarity suffix.

by
  پت   
pat

Fr.: par   

A preposition used to indicate the agent after a passive verb. By means of.

M.E., O.E. bi "near, in, by, during, about;" cf. O.S. and O.Fr. bi, M.Du., Du. bij, Ger. bei;cf. Skt. abhi "toward, to," Gk. amphi- "around, about;" Av. aibi, aiwi, O.Pers. aiby, Pers. af-.

Pat, from Mid.Pers. pat, pad "to, at, in, on" (Mod.Pers. ); O.Pers. patiy, Av. paiti "to, at, for, with, by mean of," cf. Skt. práti "toward, against, again, back, in return, opposite;" Pali pati-; Gk. proti, pros "face to face with, toward, in addition to, near;" PIE *proti.

by default
  پت نابون   
pat nâbun

Fr.: par défaut   

Because of a lack of opposition or alternative.

by; → default.

B[e] star
  ستاره‌یِ B[e]   
setâre-ye B[e]

Fr.: étoile B[e]   

A → Be star with → forbidden lines in emission in its spectrum. B[e] stars show large → infrared excess due to → circumstellar dust emission. See also → supergiant B[e] star, → pre-main sequence B[e] star, → compact planetary nebula B[e] star, → symbiotic B[e] star, and → unclassified B[e] star.

B, referring to the spectral type; e for emission lines, brackets for distinction from Be; → star.

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