An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



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Number of Results: 42 Search : object
abstract object
  بر‌آخت ِ آهنجیده   
barâxt-e âhanjidé

Fr.: objet abstrait   

An entity that does not exist in space or time and is not perceptible. Some examples are universals, sets, geometrical figures, and numbers.

abstract; → object.

anonymous object
  بر‌آخت ِ انام، ~ بینام   
barâxt-e anâm, ~ binâm

Fr.: objet anonyme   

An → astronomical object which has not been catalogued.

anonymous; → object.

astronomical object
  بر‌آخت ِ اخترشناسیک، ~ اختری   
barâxt-e axtaršenâsik, ~ axtari

Fr.: objet astronomique   

A naturally occurring physical entity or association that lies beyond the Earth's atmosphere and can be studied observationally. In other words, a gravitationally bound structure that is associated with a position in space, but may consist of multiple independent astronomical objects. A list of astronomical objects includes → planets, → asteroids, → comets, → stars, → nebulae, galaxies (→ galaxy), → galaxy clusters, → pulsars, and → black holes. Note that → celestial body, → celestial object, and → heavenly body are less technical terms for these entities.

astronomical; → object.

astrophysical object
  بر‌آخت ِ اخترفیزیکی   
barâxt-e axtarfiziki

Fr.: objet astrophysique   

An extraterrestrial → object whose physical properties and formation are studied in → astrophysics.

astrophysical; → object.

Becklin-Neugebauer object
  بر‌آخت ِ بکلین-نیوجباؤر   
barâxt-e Becklin-Neugebauer

Fr.: objet de Becklin-Neugebauer   

A compact infrared source in the Orion molecular cloud (OMC-1). It is thought to be a very dusty compact H II region surrounding a young B0 or B1 star.

After Eric Becklin (1940-), and Gerry Neugebauer (1932-) who discovered the object in 1967; → object.

BL Lac object
  بر‌آخت ِ BL چلپاسه   
barâxt-e BL Calpâsé

Fr.: objet BL Lac   

A member of a family of → quasars, or extragalactic → Active Galactic Nuclei, which displays a high radio emission and/or important optical variability over a short period of time. BL Lac objects appear star-like but their spectrum is flat, and partially polarized. Also called → blazars.

BL Lac, from object BL in the constellation → Lacerta (BL Lacertae). The reason for this terminology is that it was originally thought to be an irregular variable star in our Galaxy; hence its variable star designation. In the 1970s the "star" was identified with a bright, variable → radio source and a very faint galaxy; → object.

celestial object
  بر‌آخت ِ آسمانی   
barâxt-e âsmâni

Fr.: objet céleste   

astronomical object.

celestial; → object.

compact central object (CCO)
  بر‌آخت ِ همپک ِ مرکزی   
barâxt-e hampak-e markazi

Fr.: objet compact central   

An → X-ray source detected close to the center of young → supernova remnant (SNR)s that has no apparent emission in other wave-bands and no binary companions. Although these sources have been known and studied for several decades without much understanding of their nature, exciting results over the past few years have brought them into the forefront of → neutron star studies. They have soft, exclusively thermal spectra in the few hundred eV range and X-ray luminosities around 1033 - 1034 erg s-1. About ten CCOs are presently known, including the central sources of CasA, Puppis A and Kes 79 supernova remnants. Several, J1852+0040 in Kes79, J0822.0-4300 in Puppis A and 1E 1207.4-5209 in PKS 1209-51/52, have detected pulsations in the hundreds of milliseconds range. J1852+0040 has a detected → period derivative, indicating that it is spinning down like a → rotation-powered pulsar (RPP). The measured period and either measurements or constraints on period derivative indicate that these sources have very low → magnetic fields in the range 1010 - 1011 G assuming magnetic dipole braking. Since their SNRs are all young, ~ 103 - 104 yr, they were probably born with unusually low magnetic fields, which makes them "anti-magnetars" (A. K. Harding, 2013, Front. Phys. 8, 679 and references therein).

compact; → central; → object.

compact object
  بر‌آخت ِ همپک   
barâxt-e hampak

Fr.: objet compact   

An astronomical object that is substantially denser or more compact than most objects of its class. More specifically, a → neutron star or a → stellar black hole.

compact; → object.

eruptive object
  بر‌آخت ِ اسدرشی   
barÂxt-e osdareši

Fr.: objet éruptif   

An astronomical object such as a → variable star, a → nova, a → young stellar object, etc. characterized by abrupt changes of luminosity.

eruptive; → object.

extended object
  بر‌آخت ِ استنیده   
barâxt-e ostanidé

Fr.: objet étendu   

An object whose angular size exceeds the resolution of the instrument used to observe it.

extended; → object.

field object
  بر‌آخت ِ میدان   
barâxt-e meydân

Fr.: objet de champ   

An astronomical object that is seen in the direction of a group but not physically belonging to the group. → field galaxy.

field; → object.

free-floating objects
  بر‌آخت‌های ِ شناور   
barâxthâ-ye šenâvar

Fr.: objets flottants   

A population of → substellar objects which are not bound to stars; they are detected in young star clusters. Their masses, estimated from their fluxes, is several Jupiter masses, lower than those of → brown dwarfs. Their formation is not yet explained. Among the envisaged possibilities: 1) These objects form like stars, from protostellar core collapse and subsequent accretion; 2) they form as low-mass members of small groups, and are ejected from the group; 3) they form like planets within circumstellar disks of higher-mass objects, but are ejected either due to internal dynamics or external interactions.

free; floating, from M.E. float, from O.E. flotian "to float" (cf. O.N. flota, M.Du. vloten); → object.

Barâxt, → object; šenâvar "that swims, floats," from šenâ "swimming;" Mid.Pers. šnâz "swim," šnâzidan "to swim;" Av. snā- "to wash, swim;" cf. Skt. snā- "to bathe, to wash;" L. nare, natare "to swim" (Fr. nage, nager, natation; Sp.nadar, natacion).

FU Orionis object
  بر‌آخت ِ FU شکارگر   
barâxt-e FU Šekârgar

Fr.: objet FU Orionis   

A member of a class of → pre-main sequence stars that experience dramatic changes in magnitude and → spectral type. During an outburst the luminosity of such an object can increase by several orders of magnitude on short time-scales (few months to few years). The phenomenon is explained by abrupt mass transfer from an → accretion disk to a young, low mass → T Tauri star (accretion rates 10-4 to 10-3 solar masses per year). → EX Lupi; → Z CMa.

F and U, alphabet letters; Orionis, → Orion; → object.

Herbig-Haro object
  بر‌آخت ِ هربیگ-هارو   
barâxt-e Herbig-Haro

Fr.: objets Herbig-Haro   

A small patch of → nebulosity in a → star-forming region, created when fast-moving → jets of material (with speeds up to about 1000 km per sec) from a newborn star collide with the → interstellar medium.

Herbig AeBe star; Guillermo Haro (1913-1988), who first in 1940s studied these objects in detail and recognized that they were a by-product of the star formation process; → object.

high redshift object
  بر‌آخت ِ مه-سرخ‌کیب   
barâxt-e meh-sorxkib

Fr.: objet à grand décalage vers le rouge   

A galaxy or quasar having a → redshift larger than about 0.8, corresponding to a → look-back time half the present age of the Universe. The qualifier "high" is, however, relative and depends on context and authors' assessment.

high; → redshift; → object.

inner Earth object (IEO)
  بر‌آخت ِ درونی ِ مدار ِ زمین   
barâxt-e daruni-ye madâr-e zamin

Fr.: objet interne à l'orbite terrestre   

A → near-Earth object whose → orbit lies always inside Earth's orbit.

inner; → Earth; → object.

Kuiper belt object (KBO)
  بر‌آخت ِ کمربند ِ کویپر   
barâxt-e kamarband-e Kuiper

Fr.: objet de la ceinture de Kuiper   

A → Solar System object belonging to the → Kuiper belt. The largest known objects of this type are → Pluto and its moon → Charon, → Quaoar, → Sedna, and → Orcus. See also → trans-Neptunian object.

Kuiper belt; → object.

lensing object
  بر‌آخت ِ لنزنده   
barâxt-e lenzandé

Fr.: objet amplificateur   

An astronomical object that creates → gravitational lensing. See also → lensing galaxy.

lensing; → object.

mathematical object
  بر‌آخت ِ مزداهیک، ~ ریاضی   
barâxt-e mazdâhik, ~ riyâzi

Fr.: objet mathématique   

An → abstract object dealt with in mathematics that has a definition, obeys certain properties, and can be the target of certain operations. It is often built out of other, already defined objects. Some examples are → numbers, → functions, → triangles, martices (→ matrix), → groups, and entities such as → vector spaces, and → infinite series.

mathematical; → object.

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