The River. An extensive constellation in the southern hemisphere that takes windings between 1h20 and 5h 10m right ascension, 0° to 58° south declination. Despite its size, there are not many bright stars in this constellation. Notable are → Achernar and ε Eri, a dwarf star of magnitude 4.6 and type K2, which is just 10.7 light years away. Abbreviation: Eri; genitive: Eridani.
From Gk. Eridanos, a river god, a son of Oceanus and Tethys, and father of Zeuxippe. A purely mythical river which may have been named Eridanos ("Early Burnt") from the story of Phaethon, the boy who attempted to drive the chariot of the sun, and fell flaming into the waters of this mythical river.
Rud, → river.
A → dwarf planet which is a → trans-Neptunian object (TNO) with an orbital → eccentricity of 0.44, an → inclination of 44 degrees and a surface composition very similar to that of → Pluto. It orbits the Sun as far as twice Pluto's distance from the Sun. → Occultation observations carried out in 2010 were used to measure the size of Eris accurately. Eris's newly determined diameter is 2326±12 km. The observations show that Eris is an almost perfect twin of Pluto in size. They also reveal a very reflective surface, with an → albedo of 0.96, suggesting that it is uniformly covered in a thin layer of ice, probably a frozen atmosphere (Sicardy et al. 2011, Nature 478, 493). Like Pluto, Eris has a moon, which has been officially named by the → International Astronomical Union as (136199) Eris I (→ Dysnomia). The informal names of Eris were Xena and 2003 UB313.
Named after Eris the Gk. goddess of chaos and strife. She created a quarrel among goddesses that led to the Trojan War.
The act or state of eroding; state of being eroded.
From M.Fr. erosion, from L. erosionem (nom. erosio), from erodere "to gnaw away," from → ex- "away" + rodere "to gnaw, eat away" (cf. Fr. and E. animal rat).
Farsâyeš, from far- intensive prefix "much, abundant" (Mid.Pers. fra- "forward, before; much; around;" O.Pers. fra- "forward, forth;" Av. frā, fərā-, fra- "forward, forth; excessive;" cf. Skt. prá- "before; forward, in fron;" Gk. pro "before, in front of;" L. pro "on behalf of, in place of, before, for;" PIE *pro-) + verbal noun of sâyidan, variants sâbidan "to bruise, file," pasâvidan "to touch;" Khotanese sauy- "to rub;" Sogdian ps'w- "to touch;" Proto-Iranian *sau- "to rub."
Same as → Gamma Cephei.
From Ar. ar-râ'i (
irang (#), xatâ (#)
1) A deviation from accuracy or correctness; a mistake.
From O.Fr. erreur, from L. errorem (nom. error) "a wandering, straying, mistake," from errare "to wander."
Irang, from Mid.Pers. êrang "error, mistake;" xatâ, from Ar.
band-e irang, ~ xatâ
Fr.: barre d'erreur
On a graph displaying the results of a measurement, the dash used to indicate the confidence range of the value attributed to a quantity.
→ error; bar, from O.Fr. barre, from V.L. *barra "bar, barrier," or perhaps from Gaulish *barro "summit."
Band "that which closes, shuts, blocks," from bastan, band- "to shut, bind," from Mid.Pers. bastan/vastan "to bind, shut," Av./O.Pers. band- "to bind, fetter," banda- "band, tie" (cf. Skt. bandh- "to bind, tie, fasten," PIE *bhendh- "to bind;" Ger. binden; E. bind); → error.
Fr.: entrer en éruption
To burst forth; to eject matter (of a star, volcano, geyser, etc.). → eruptive variable.
From L eruptus "burst forth, broken out," p.p. of erumpere "to break out, burst forth," from → ex- "out" + rumpere "to break, rupture."
Osdaridan, from os-, → ex- + daridan "to tear, rend, lacerate;" Mid.Pers. darridan "to tear, split;" Av. dar- "to tear," dərəta- "cut," auua.dərənant- "shattering;" cf. Skt. dar- "to crack, split, break, burst," darati "he splits;" Gk. derein "to flay," derma "skin;" P.Gmc. *teran; O.E. teran; E. tear; Ger. zerren "to pull, to tear," zehren "to undermine, to wear out;" PIE base *der- " to split, peel, flay."
1) An act, process, or instance of erupting; something that is erupted or ejected.
Verbal noun of → erupt.
Relating to, formed by, characterized by, or producing → eruption.
Fr.: objet éruptif
Fr.: protubérance éruptive
A huge solar prominence which has previously been quiescent but suddenly starts to lift up from the → photosphere with velocities of several hundred km/s and escapes into the → interplanetary space. Eruptive prominences with the highest velocities have been observed at 1300 km/s, reaching heights of 1 million km above the photosphere. Such prominences are often observed at the solar limb, in association with → coronal mass ejections. On the Sun's disk, the equivalent phenomenon is an eruptive filament.
Fr.: variable éruptive
same as → cataclysmic variable.
1) gorixtan, 2) goriz (#)
Fr.: 1) échapper, s'échapper; 2) échapement
1) To get away; to get free of.
From M.E. escapen; O.Fr. eschaper, from V.L. *excappare, literally "to get out of one's cape, leave a pursuer with just one's cape," from L. → ex- "out" + L.L. cappa "mantle."
Gorixtan, goriz- "to escape; to flee, run away;" Mid.Pers. virextan; Proto-Iranian *vi-raik, from vi- "apart, asunder" + *raik; Av. raek- "to leave, set free, let off;" Mid./Mod.Pers. reg/rig (in mordé-rig "inheritance"); Skt. ric- "to leave," rinakti "gives up, evacuates;" Gk. leipein "to leave;" L. linquere "to leave;" from PIE *linkw-, from *leikw- "to leave behind" (cf. Goth. leihvan; O.E. lænan "to lend;" O.H.G. lihan "to borrow;" O.N. lan "loan").
Fr.: vitesse d'échapement
The speed an object must attain in order to free itself from the gravitational influence of an astronomical body. It is the minimum velocity for the object to enter a parabolic trajectory. The escape velocity is given by: Ve = (2GM/r)1/2, where G is the → gravitational constant, M is the mass of the astronomical body, and r is its radius. The escape velocity of the Earth is about 11.2 km s-1, that of the Moon is 2.4 km s-1, and that of the Sun about 618 km s-1.
An advanced stellar → spectropolarimeter designed and built at the Observatoire Midi-Pyréenées and installed at the → Canada-France-Hawaii Telescope (CFHT). It can obtain a a complete optical spectrum, from 370 nm to 1050 nm, in a single exposure. Among its characteristics: resolving power 65 000 to 80 000; 12% peak throughput (telescope and detector included); continuum subtracted linear and circular polarization spectra of the stellar light (in polarimetric mode). ESPaDOnS is used to study a broad range of important problems in stellar physics: from → stellar magnetic fields to → accretion disks and → extrasolar planets; from inhomogeneities and differential rotation on stellar surfaces to activity cycles and magnetic braking; from microscopic diffusion to turbulence, convection, and circulation in stellar interiors; from abundances and pulsations in stellar atmospheres to stellar winds; from the early phases of stellar formation to the late stages of stellar evolution; from extended circumstellar environments to distant interstellar medium (Donati et al., 2006, Solar Polarization, ASP Conf. Series, 358, 362, eds. R. Casini, B. W. Lites).
1) To found, institute, build, or bring into being on a firm or stable basis.
From O.Fr. establiss-, stem of establir, from L. stabilire "make stable," from stabilis "firm, stable," literally "able to stand," from stare "to stand;" PIE base *sta- "to stand" (cf. Mod.Pers. istâdan "to stand;" O.Pers./Av. sta- "to stand, stand still; set;" Skt. sthâ- "to stand;" Gk. histemi "put, place, weigh;" stasis "a standing still;" Lith. statau "place;" Goth. standan; O.E. standan "to stand," stede "place").
Nešâxtan, nešâzidan "to establish; to fix in the ground, strengthen," from ne- "down, below," → ni-, + šâxtan, šâz-, variants of Mod./Mid.Pers. sâxtan, sâz- "to form, prepare, build, make," ultimately from Proto-Iranian *sac- "to fit, be suitable; to prepare."
Fr.: 1, 2, 3, 4) établissement; 4) les pouvoirs établis
1) The act or an instance of establishing.
1) arj (#); 2) arj nehâdan
Fr.: 1) estime; 2) estimer
1) Favorable opinion or judgment; respect or regard.
M.E. estemen, from M.Fr. estimer, from L. aestimare "to value, determine the value of, appraise," → estimate.
Fr.: estimable, digne d'estime
Worthy of esteem; deserving respect or admiration. Capable of being estimated (Dictionary.com).
1) barâvard (#); 2) barâvardan (#), barâvard kardan (#)
Fr.: 1) estimation; 2) estimer
1) Statistics: An indication of the value of an unknown quantity based
on observed data.
From M.Fr. estimer, from L. æstimatus, p.p. of æstimare "to value, estimate."