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

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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<< < -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
Hill sphere
  سپهر ِ هیل   
sepehr-e Hill

Fr.: sphère de Hill   

The spherical region around a → secondary in which the secondary's gravity is more important for the motion of a particle about the secondary than the tidal influence of the → primary. The radius is described by the formula: r = a (m/3M)1/3, where, in the case of the Earth, a is the semi-major axis of the orbit around the Sun, m is the mass of Earth, and M is the mass of the Sun. The Hill sphere for the Earth has a radius of 0.01 → astronomical units (AU). Therefore the Moon, lying at a distance of 0.0025 AU, is well within the Hill sphere of the Earth.

Named for George William Hill (1838-1914), an American astronomer who described this sphere of influence; → sphere.

Hill stability
  پایداری ِ هیل   
pâydâri-ye Hill

Fr.: stabilité de Hill   

The condition for the stability of a → three-body system. Three-body systems exist widely in the → solar system and → extrasolar systems, including Sun-planet-moon systems, planets-star systems, and → triple star systems. This concept of stability was introduced by Hill (1878). He used the → Jacobi integral to construct bounds of motion for → conservative systems with time-independent → potentials, which was introduced to study the stability of the Moon in the Sun-Earth → restricted three-body problem. The stability is defined by the → zero-velocity surface based on the Jacobi integral. The concept of the Hill stability has been used by many researchers to study the stability of three-body systems. The studies include the Hill stability in the full → three-body problems, the hierarchical three body problems, and the restricted three body problems (See, e.g., S. Gong & J. Li, 2015, Astrophys Space Sci. 358,37).

Hill, G.W.: Researches in the lunar theory. Am. J. Math. 1(2), 129-147 (1878); → stability.

Himalia (Jupiter VI)
  هیمالیا   
Himâliyâ (#)

Fr.: Himalia   

The tenth of Jupiter's known satellites, 186 km in diameter revolving at a mean distance of 11,480,000 km from Jupiter. Discovered in 1904 by the Argentine-American astronomer Charles Dillon Perrine (1867-1951).

Himalia was a nymph of the island of Rhodes. She was seduced by the god Zeus (Jupiter).

Hindu-Arabic numeral system
  راژمان ِ عددهای ِ هندی-عربی   
râžmân-e adadhâ-ye Hendi-Arabi

Fr.: numération indo-arabe   

Same as → Indian numeral system.

numeral; → system.

hip
  شنج   
šanj (#)

Fr.: hanche   

O.E. hype "hip," akin to Du. heup, O.H.G. huf, Ger. Hüfte, Swed. höft, Goth. hups "hip," of uncertain origin.

Šanj (Dehxodâ) "hip, buttock, thigh, haunch," of unknown origin.

Hipparcos
  هیپارکوس   
Hipparcos (#)

Fr.: Hipparcos   

A → European Space Agency satellite, which was launched in August 1989 and operated until March 1993. It was the first space mission devoted to → astrometry with an unprecedented degree of accuracy. The telescope on Hipparcos had a main mirror of diameter 29 cm. Calculations from observations by the main instrument generated the Hipparcos Catalogue of 118,218 stars charted with the highest precision (published in 1997) containing positions, distances, → parallaxes, and → proper motions. An auxiliary star mapper pinpointed many more stars with lesser but still unprecedented accuracy, in the Tycho Catalogue of 1,058,332 stars. The Tycho 2 Catalogue, completed in 2000, brings the total to 2,539,913 stars, and includes 99% of all stars down to magnitude 11. → Gaia.

Hipparcos, acronym for → High  → Precision  → Parallax  → Collecting → Satellite, chosen for its similarity to the name of the Greek astronomer Hipparchus of Nicaea (c. 190-125 BC), one of the most influential astronomers of antiquity, who compiled an extensive star catalogue in which he gave the positions of over 1,000 stars and also classified them according to their magnitude (on a scale of 1 to 6, brightest to faintest). Ptolemy later incorporated this information into his → Almagest. In addition, he discovered the → precession of the equinoxes.

Hippocamp
  هیپوکامپ   
Hipokâmp

Fr.: Hippocampe   

The smallest known moon orbiting the planet → Neptune, discovered in 2013. Hippocamp has an estimated diameter of only about 34 km and orbits close to → Proteus, the outer and the second largest of Neptune's moons. The orbital → semi-major axes of the two moons differ by only 10%. Hippocamp is probably an ancient fragment of Proteus. Billions of years ago a comet collision would have chipped off a chunk of Proteus. Images from the Voyager 2 space probe from 1989 show a large → impact crater on Proteus, whose size compares with Hippocamp's (Showalter et al., 2019, Nature 566, 350).

Formerly known as S/2004 N 1, Hippocamp is named after the sea creatures in Greek and Roman mythology. The mythological Hippocampus possesses the upper body of a horse and the lower body of a fish. The Roman god Neptune would drive a sea-chariot pulled by Hippocampi.

hippopede
  هیپوپد   
hipoped

Fr.: hippopède   

A curve described by the → polar equation  r2 = 4b (a - b sin2θ), where a and b are positive constants. For appropriate values of a and b, the curve looks like the infinity symbol, ∞. See also → spheres of Eudoxus.

Hippopede, literally "a horse's foot," denoting a "horse fetter (hobble)," from Gk. hippos, → horse, + -pede variant of -ped, combining form of pos,→ foot.

histogram
  نمودار ِ ستونی   
nemudâr-e sotuni (#)

Fr.: histogramme   

A type of graphical representation, used in statistics, in which frequency distributions are illustrated by rectangles.

Histogram, from Gk. histo-, a combining form meaning "tissue," from histos "mast, loom, beam, warp, web," literally "that which causes to stand," from histasthai "to stand," from PIE *sta- "to stand" (cf. Pers. ist-, istâdan "to stand;" O.Pers./Av. sta- "to stand, stand still; set;" Skt. sthâ- "to stand;" L. stare "to stand;" Lith. statau "place;" Goth. standan); → -gram.

Nemudâr, → diagram + sotuni "column-like," from sotun "column," from Mid.Pers. stun, from O.Pers. stênâ "column," Av. stuna-, Skt. sthuna- "column."

historical
  تاریخی   
târixi (#)

Fr.: historique   

Of, pertaining to, treating, or characteristic of → history or past events (Dictionary.com). → historical supernova.

history; → -al.

historical supernova
  اَبَر-نو‌اَختر ِ تاریخی   
abar-now-axtar-e târixi (#)

Fr.: supernova historique   

A supernova event recorded in the course of history before the invention of the telescope. The well recorded supernovae of this small group are SN 185, SN 1006, SN 1054 (→ Crab Nebula), SN 1181, SN 1572 (→ Tycho's star), and SN 1604 (→ Kepler's star).

historical; → supernova.

history
  تاریخ   
târix (#)

Fr.: histoire   

1) The branch of knowledge dealing with past events.
2) The record and explanation of past events and times, especially in connection with a particular people, country, period, person, etc. See: → star formation history, → historical supernova.

History, from M.E. histoire, historie, from O.Fr. estoire, histoire, from L. historia "narrative, tale, story," from Gk. historia "a learning or knowing by inquiry, record, account," from historein "to inquire," from histor "one who knows or sees, wise man, " from PIE *wid-tor-, from base *weid- "to know; to see;" cf. Pers. bin- "to see" (present stem of didan); Mid.Pers. wyn-; O.Pers. vain- "to see;" Av. vaēn- "to see;" Skt. veda "I know." Related to Gk. idein "to see," and to eidenai "to know," → idea.

Târix, from Ar., itself, according to Abu Rayhân Biruni (973-1048, in Athar al-Baqqiya), loan from Mid.Pers. mâhrôz "date," first Arabicized as murux, from which the infinitive taurix, and then târix.

hoarfrost
  بشم   
bašm (#)

Fr.: givre, gelée   

Another name for → frost.

Hoba meteorite
  شهابسنگ ِ هوبا   
šahâbsang-e Hoba

Fr.: météorite d'Hoba   

The world's largest meteorite found in 1920, near Grootfontein, Namibia. It was discovered by Jacobus H. Brits while ploughing one of his fields with an ox. The meteorite is tabular in shape and measures 2.95 x 2.84 m; it has an average thickness of about 1 m (1.22 m maximum and 0.75 m minimum). The Hoba meteorite weighs about 65-70 tons. Its chemical composition is 82.4 % iron, 16.4 % nickel, 0.8 % Cobalt, and traces of other metals. No crater is present around the site of the meteorite, probably because it fell at a lower rate of speed than expected. The flat shape of the object may be responsible for its low velocity at impact.

Named after Hoba West, the farm it was discovered; → meteorite.

Hohmann transfer
  تراوژ ِ هوهمن   
tarâvaž-e Hohmann

Fr.: transfert de Hohmann   

An → orbital maneuver using two timed engine impulses to move a spacecraft between two coplanar circular orbits. It is performed through an elliptic orbit which is tangent to both circles at their periapses (→ periapsis).

In honor of Walter Hohmann (1880-1945), German engineer who in his book, The Attainability of Celestial Bodies (1925), described the mathematical principles that govern space vehicle motion, in particular spacecraft transfer between two orbits.

hole
  سوراخ، چاله، چال   
surâx (#), câlé (#), câl (#)

Fr.: trou   

1) General: An opening through something; an area where something is missing; a serious discrepancy.
2) Astro.: → black hole; → coronal hole.
3) Electronics: The absence of an electron in the valency structure of a crystalline semiconductor, behaving like a positive charge carrier.

O.E. hol "orifice, hollow place," from P.Gmc. *khulaz (cf. O.H.G. hol, M.Du. hool, Ger. hohl "hollow"), from PIE base *kel- "to cover, conceal." → cell.

Surâx "hole," from Mid.Pers. sûlâk "whole, aperture," Av. sūra- "hole;" cf. Gk. koilos "hollow," L. cava "cave," cavus "hollow;" PIE base keuə- "to swell; vault, hole."
Câlé, câl "hole," from câh "a well, pit," from Mid.Pers. câh "a well;" Av. cāt- "a well," from kan- "to dig," uskən- "to dig out" (O.Pers. kan- "to dig," akaniya- "it was dug;" Mod.Pers. kandan "to dig"); cf. Skt. khan- "to dig," khanati "he digs," kha- "cavity, hollow, cave, aperture."

hole injection
  درشانش ِ سوراخ، ~ چاله   
daršâneš-e surâx, ~ câlé

Fr.: injection de trou   

The injection of holes in a semiconductor which can be produced by application of a sharp conducting point in contact with an n-type semiconductor.

hole; → injection.

holiday
  ۱) سپنت‌روز؛ ۲) آسودروز؛ ۳) آسودگان   
1) sepantruz; 2) âsudruz; 3) âsudgân

Fr.: 1); 2) férié; 3) vacances   

1) A day fixed by law or custom on which ordinary business is suspended in commemoration of some event or in honor of some person.
2) Any day of exemption from work.
3) (in plural form) A period of cessation from work or one of recreation; vacation.

O.E. haligdæg, from halig "holy," → heiligenschein, + dæg, → day.

1) Sepantruz, from sepant "holy," → heiligenschein, + ruz, → day.
2) Âsudruz, from âsud, âsudan "to rest, repose," from Mid.Pers. âsutan, Av. ā- + saē- (saii-) "to lie down, go to sleep;" + ruz, → day.
3) Âsudgân, from âsud, as before, + -gân suffix forming plurals.

holo-
  هرو-   
haru- (#)

Fr.: holo-   

A combining form meaning "complete, entire, total, whole," used in the formation of compound words: → holonomic, → holography, holomorphic.

From M.E. holo-, from O.fr., from L. hol-, holo-, from Gk. holos "whole," akin to Pers. har- "every, all, each, any," as below.

Haru, from Mid.Pers. har(v) "all, each, every" (Mod.Pers. har "every, all, each, any"); O.Pers. haruva- "whole, all together;" Av. hauruua- "whole, at all, undamaged;" cf. Skt. sárva- "whole, all, every, undivided;" Gk. holos "whole, complete;" L. salvus "whole, safe, healthy," sollus "whole, entire, unbroken;" PIE base *sol- "whole."

holocaust
  هروسوچ   
harusuc

Fr.: holocauste, shoa   

1) A great or complete devastation or destruction, especially by fire.
2) (usually initial capital letter, preceded by the) The systematic mass slaughter of European Jews in Nazi concentration camps during World War II (Dictionary.com).

M.E., from L.L. holocaustum, from Gk. holokaustos "burnt whole;" see → holo- "complete, entire, total," → caustic "burning; burnt."

Harusuc "entirely burnt;" → holo-, → caustic "burning; burnt."

<< < -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 > >>