An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

<< < -es -iv -ti 21- A r abe abs abs acc acc acc act act ada adi adu aff age alc Alf ali all alp alt ama amp ana ang ang ann ano ant ant ape apo app aps arc Arg ari art ass ast ast ast atm ato att aur aut axi B r bac Bal Bar Bar Bay bec Ber Bet Bie bij bin bio bis bla bla blu blu bol Bor bou Bra bre bro Bug C-s cal Cam can car Car Cas cat cav cel cen cer Cha cha cha che cho cir cir cir cla clo clo clu coa coe coh col col col com com com com com com com com com con con con con con con con con con con con coo cor cor cor cos cos cos Cou cou Cra Cre cri cro cub cur cyc cyl dar dat daw de- Deb dec dec dee def deg del Den dep der det deu dew dic dif dif dil dip dir dis dis dis dis dis div dog Dop dou dra dua dus dwa dyn e-m ear ecl eco eff ein Ein elb ele ele ele ele Els emi emp ene enr env epi equ equ Eri est Euc eva evo exc exc exh exo exp exp ext ext f-n Fah fam fau fee Fer fib fil fin fir fix fle flu foc for for for fra fre fre fri fun fuz gal gal gal Gan gau GCN gen geo geo geo geo Gl glo gra gra gra gra gra gre gro GW1 hab hal han HAR haz hea hel hel Hen Her heu Hig Hil hol hop hor hou Hub Hum Hyd hyd hyd hyp hys ide ign ima imp imp inc inc ind ine inf inf inf inh INP ins ins int int int int Int int int int inv ion iri irr iso iso iso Jea Jos Jun K2 Kep key kin Kol lag lam Lan lar las lav lea leg len lev lig lim lin lin lin lis lob loc log lor low lum lun lun Lym Mac mag mag mag mag mag mai Mal mar mas mas mat max mea mea mee Men mer met met met mic mid Mil min Mir mix mod mod mol mon Mor mou mul muo mys nan nat nav nec Nep neu New New NGC nob nom non non nor not nuc nuc num Nyq obj obs obs oce oen OH omn opa ope opt opt opt orb ord Ori ort osc out ove oxy pal pan par Par par par pas pea Pen per per per per per pet pha pho pho pho phy pie Pit Pla pla pla pla ple Poi pol pol pol pol pop pos pos pow pre pre pre Pre pri pri pri pro pro pro pro pro pro Pro pub pul pyr qua qua qua qua Qui rad rad rad rad rad rad ram ran rat rea rec rec rec red ref ref reg reg rel rel rem rep res res res ret rev rho Rie rim riv rol Ros rot rul S a Sah san Sat sca Sch Sch scr sec sec sec sei sel sem sep set sha she sho sid sig sil sim sin sit sky slu sno sof sol sol sol sol sou sou spa spa spe spe spe sph spi spl spr sta sta sta sta sta ste ste sti sto str str sub sub sub sug sun sup sup sup sup sur syl syn sys tal Tay tel ten ter tex the the the thi tho thu tid tim tod top tot tra tra tra tra tri tri tro tru tur twi Typ UFO ult unc uni uni uni upg ura uti val var vec vel ver ver vig vir vis voc von wak Was wav wax wea wei whi Wie win WN6 wom X-r yel you zer zod > >>

Number of Results: 12948 Search : far
A ring
  حلقه‌ی ِ A   
halqe-ye A

Fr.: anneau A   

One of → Saturn's rings, lying beyond the → B ring at 122,170 km from the center of Saturn, with a width of 14,600 km.

ring.

A star
  ستاره‌ی A   
setâre-ye A

Fr.: étoile de type A   

A star whose spectrum shows strong hydrogen → Balmer lines accompanied by many faint to moderately strong metallic lines. In contrast to B and O stars, the lines of He I and He II are absent. Their surface temperature ranges from 7,500 to 10,000 K. The main metallic lines seen in A-type stars are those of Fe I and Fe II, Cr I and II, Ti I and II, and account for about two-thirds of all lines. Some famous examples of A star are: → Sirius; → Deneb, → Altair, and → Vega. Also known as A-type star.

A, letter of alphabet used in the → Harvard classification; → type; → star.

a-
  ا-، ان-؛ بی-؛ نا-   
a- (#), an- (#); bi- (#); nâ- (#)

Fr.: a-   

Prefix meaning "not."

From Gk. a-, an- "not," compare with O.Pers./Av. a-, an- "not, without," Skt. a-, an- "not," L. in-, a variant of PIE *ne- "not".

A-, an-, from O.Pers./Av. negation prefix appearing before consonants and vowels respectively. A couple of examples in Mod.Pers.: amordâd "immortality, name of the fifth month in the Iranian calendar," anušé; "fortunate, happy," anirani "non Iranian," âhu "vice, defect," âsoqdé "unburnt, half-burnt wood."
Bi- privative prefix, from Mid.Pers. abi-, O.Pers. *apaiy-, Av. apa-.
Nâ- negation prefix "not, no," Mid.Pers. ne, O.Pers. naiy, Av. na-, (particle of negation noit), Skt. na-, (ned), Gk. né- "not," L. ne-, in-, un-, PIE *ne-.

A-type star
  ستاره‌ی ِ گونه‌ی ِ A   
setâre-ye gune-ye A

Fr.: étoile de type A   

Same as → A star.

A, letter of alphabet used in the → Harvard classification; → type; → star.

A/2017 U1
     
A/2017 U1

Fr.: A/2017 U1   

1I/'Oumuamua.

asteroid designation.

Aarau paradox
  پارادخش ِ آراؤ   
pârâdaxš-e Aarau

Fr.: paradox d'Aarau   

A → thought experiment conceived by Einstein (1879-1955) at the age of sixteen in the Swiss town of Aarau where he attended the Argovian cantonal school. If an → observer moved at the → speed of light, pursuing a → beam of light, would he → observe such a beam of light as a spatially oscillatory → electromagnetic field at rest? The answer came some ten years later from Einstein himself by his theory of → special relativity. Accordingly, the speed of light is constant for all observers and no observer can move at the light velocity.

Aarau, the Swiss town, the capital of the northern Swiss canton of Aargau; → paradox.

AB Doradus
     
AB Doradus

Fr.: AB Doradus   

A → quadruple system of stars consisting of two close pairs, AB Dor A / AB Dor C and AB Dor Ba / AB Dor Bb, separated by about 9 arcseconds. The brightest star of the system, AB Dor A, is a → pre-main sequence star of → spectral type K1, with strong emission at all wavelengths, from radio to X-rays. The companion of this star, i.e. component C, lying 0.185 arcseconds apart, is a very low-mass star of 0.090 → solar masses with a spectral type M 5.5 (Boccaletti et al. 2008, A&A 482, 939 and references therein).

A, a, B, b, and C designating letters of alphabet; → Dorado.

ab initio
  هچ بن   
hac bon

Fr.: ab initio   

"From the beginning," as opposed to in medias res "starting in the middle of the story." In physics and chemistry "from first principles;" → ab initio calculation.

L. "from the beginning," from ab "from," → ab- + initio, ablative of initium "a beginning, an entrance<," from inire "to go into, begin," from in- "into, in" + ire "to go" (cf. Gk. ienai "to go," Skt. eti "goes," O.Pers. aitiy "goes," Av. aeiti "goes," Mod.Pers. âyad "comes," PIE *ei- "to go, to walk").

Hac bon, from Mid.Pers. hac "from" (O.Pers. hacā "from," Av. hacā "from, out of," cf. Skt. sácā "with," PIE base *sekw- "to follow," Av. hac-, hax- "to follow," hacaiti "follows," Skt. sácate "accompanies, follows," Gk. hepesthai "to follow," L. sequi "to follow," Lith. seku "to follow") + bon "beginning, base, root" (Av. būna- "base, depth," cf. Skt. bundha-, budhná- "base, bottom," Pali bunda- "root of tree").

ab initio calculation
  افمار ِ هچ بن   
afmâr-e hac bon

Fr.: calcul ab initio   

In physics and chemistry, a calculation that relies on basic and established laws without additional assumptions or special models. Experimental input in ab initio calculations is limited to the determination of values of fundamental physical constants.

ab initio; → calculation.

AB magnitude system
  راژمان ِ بُرز ِ BA   
râžmân-e borz-e AB

Fr.: système de magnitudes AB   

A → photometric system defined by reference to → monochromatic magnitudes in such a way that, when monochromatic → flux fν is measured in ergs sec-1 cm-2 Hz-1, the magnitude will be: AB = -2.5 logfν - 48.60. The constant is set so that AB is equal to the V magnitude for a source with a flat → spectral energy distribution. The → zero point is defined by the flux of the star → Vega at 5546 Å. In this system, an object with constant flux per unit frequency interval has zero color.

magnitude; → system.

abandon
  راچیدن   
râcidan

Fr.: abandonner   

1) To leave completely and finally; forsake utterly; desert.
2) To give up; discontinue; withdraw from (Dictionary.com).

M.E. abando(u)nen, from M.Fr. abandoner, from O.Fr. abandoner from adverbial phrase à bandon "at will, at discretion," from à "at, to," → ad-, + bandon "power, jurisdiction," from L. bannum "proclamation."

Râcidan, related to Pers. parhêz, parhiz "to keep away from, abstain, avoid," gurêz, goriz "to flee, run away;" Av. raēc- "to leave, let;" → heritage.

Abbe number
  عدد ِ آبه   
adad-e Abbe

Fr.: nombre d'Abbe   

The reciprocal of the → dispersive power of a substance. Also known as constringence.

Abbe sine condition; → number.

Abbe sine condition
  بوتار ِ سینوس ِ آبه   
butâr-e sinus-e Abbe

Fr.: condition des sinus d'Abbe   

In → geometric optics, a condition for eliminating → spherical aberration and → coma in an → optical system. It is expressed by the relationship: sin u'/U' = sin u/U, where u and U are the angles, relative to the → optical axis, of any two rays as they leave the object, and u' and U' are the angles of the same rays where they reach the image plane. A system which satisfies the sine condition is called → aplanatic.

Named after Ernst Karl Abbe (1840-1905), a German physicist; → sine; → condition.

Abbe sphere
  کره‌ی ِ آبه   
kore-ye Abbe

Fr.: sphère d'Abbe   

The → locus of the intersection of input and output → conjugate rays in an optical system satisfying the → Abbe sine condition.

Abbe sine condition; → sphere.

Abel's theorem
  فربین ِ آبل   
farbin-e Abel

Fr.: théorème d'Abel   

1) If a → power series → converges for some nonzero value x0, then it converges absolutely for any value of x, for which |x| < |x0|.
2) If a power series → diverges for some nonzero value x0, then it diverges for any value of x, for which |x| > |x0|.

Named after the Norwegian mathematician Niels Henrik Abel (1802-1829); → theorem.

Abell catalog
  کاتالوگ ِ ایبل   
kâtâlog-e Abell

Fr.: catalogue Abell   

A catalog of 4073 rich → galaxy clusters grouped by constellation and by catalog number. Published first in 1958, it contained the clusters visible from the northern hemisphere. A supplement for the southern hemisphere survey was published in 1988.

George O. Abell (1927-1983), American astronomer; → catalog.

aberrate
  بیراهیدن   
birâhidan

Fr.: s'égarer, dévier   

Diverge or deviate from the straight path; produce → aberration.

Aberrate, from aberrare "go astray," from ab- "away" + errare "to wander."

Birâhidan, from birâh "a devious path; a wanderer, who deviates, errs," from bi- "without" + râh "way".

aberration
  بیراهش   
birâheš

Fr.: aberration   

1) An imperfection in the imaging properties of a → lens or → mirror. The main aberrations are → chromatic aberration, → spherical aberration, → coma, → astigmatism, → distortion, and → field curvature.
2) → aberration of starlight.
See also: → aberration angleaberration constanaberration of starlightaberration orbitannual aberrationchromatic aberrationconstant of aberrationdiurnal aberrationoptical aberrationplanetary aberrationrelativistic aberrationsecular aberrationspherical aberrationstellar aberration.

Aberration, from L. aberrationem, from aberrare "go astray," → aberrate.

Birâheš, from birâidan, → aberrate.

aberration angle
  زاویه‌ی ِ بیراهش   
zâviye-ye birâheš

Fr.: angle d'aberration   

The angle tilt required by the → stellar aberration phenomenon in order that a moving telescope points directly to a star.

aberration; → angle.

aberration constant
  پایا‌ی ِ بیراهش   
pâyâ-ye birâheš

Fr.: constante d'aberration   

Same as → constant of aberration.

aberration; → constant.

<< < -es -iv -ti 21- A r abe abs abs acc acc acc act act ada adi adu aff age alc Alf ali all alp alt ama amp ana ang ang ann ano ant ant ape apo app aps arc Arg ari art ass ast ast ast atm ato att aur aut axi B r bac Bal Bar Bar Bay bec Ber Bet Bie bij bin bio bis bla bla blu blu bol Bor bou Bra bre bro Bug C-s cal Cam can car Car Cas cat cav cel cen cer Cha cha cha che cho cir cir cir cla clo clo clu coa coe coh col col col com com com com com com com com com con con con con con con con con con con con coo cor cor cor cos cos cos Cou cou Cra Cre cri cro cub cur cyc cyl dar dat daw de- Deb dec dec dee def deg del Den dep der det deu dew dic dif dif dil dip dir dis dis dis dis dis div dog Dop dou dra dua dus dwa dyn e-m ear ecl eco eff ein Ein elb ele ele ele ele Els emi emp ene enr env epi equ equ Eri est Euc eva evo exc exc exh exo exp exp ext ext f-n Fah fam fau fee Fer fib fil fin fir fix fle flu foc for for for fra fre fre fri fun fuz gal gal gal Gan gau GCN gen geo geo geo geo Gl glo gra gra gra gra gra gre gro GW1 hab hal han HAR haz hea hel hel Hen Her heu Hig Hil hol hop hor hou Hub Hum Hyd hyd hyd hyp hys ide ign ima imp imp inc inc ind ine inf inf inf inh INP ins ins int int int int Int int int int inv ion iri irr iso iso iso Jea Jos Jun K2 Kep key kin Kol lag lam Lan lar las lav lea leg len lev lig lim lin lin lin lis lob loc log lor low lum lun lun Lym Mac mag mag mag mag mag mai Mal mar mas mas mat max mea mea mee Men mer met met met mic mid Mil min Mir mix mod mod mol mon Mor mou mul muo mys nan nat nav nec Nep neu New New NGC nob nom non non nor not nuc nuc num Nyq obj obs obs oce oen OH omn opa ope opt opt opt orb ord Ori ort osc out ove oxy pal pan par Par par par pas pea Pen per per per per per pet pha pho pho pho phy pie Pit Pla pla pla pla ple Poi pol pol pol pol pop pos pos pow pre pre pre Pre pri pri pri pro pro pro pro pro pro Pro pub pul pyr qua qua qua qua Qui rad rad rad rad rad rad ram ran rat rea rec rec rec red ref ref reg reg rel rel rem rep res res res ret rev rho Rie rim riv rol Ros rot rul S a Sah san Sat sca Sch Sch scr sec sec sec sei sel sem sep set sha she sho sid sig sil sim sin sit sky slu sno sof sol sol sol sol sou sou spa spa spe spe spe sph spi spl spr sta sta sta sta sta ste ste sti sto str str sub sub sub sug sun sup sup sup sup sur syl syn sys tal Tay tel ten ter tex the the the thi tho thu tid tim tod top tot tra tra tra tra tri tri tro tru tur twi Typ UFO ult unc uni uni uni upg ura uti val var vec vel ver ver vig vir vis voc von wak Was wav wax wea wei whi Wie win WN6 wom X-r yel you zer zod > >>