1) Philo.: The doctrine that all
→ knowledge of matters of fact derives from
experience and that the mind is not furnished with a set of concepts in advance of
Containing nothing; having none of the usual or appropriate contents (Dictionary.com).
M.E., from O.E. æmettig "vacant, not occupied," from æmetta "a leisure," from æ "not" + -metta, from motan "to have."
Tohi "empty," → void.
Fr.: graphe vide
Fr.: ensemble vide
A set containing no → elements.
Fr.: Univers vide
A → cosmological model based on → Einstein's field equations in which the → Universe is devoid of → matter and → radiation. There are two types of empty Universes: the → de Sitter Universe and the → Milne Universe.
Enceladus (Saturn II)
The eighth of → Saturn's known → satellites, discovered by Herschel in 1789. It is about 500 km in diameter and orbits Saturn at a mean distance of 238,000 km with a period of 1.37 days. Enceladus has the highest → albedo (> 0.9) of any body in the → Solar System. Its surface is dominated by clean ice. Geophysical data from the → Cassini-Huygens spacecraft imply the presence of a global → ocean below an ice shell with an average thickness of 20-25 km, thinning to just 1-5 km over the south polar region. There, → jets of → water vapor and icy grains are launched through fissures in the → ice. The composition of the ejected material measured by Cassini includes salts and silica dust. In order to explain these observations, an abnormally high heat power is required, about 100 times more than is expected to be generated by the natural → decay of → radioactive elements in rocks in its core, as well as a means of focusing activity at the south pole. According to simulations, the core is made of unconsolidated, easily deformable, porous rock that water can easily permeate. The → tidal friction from Saturn is thought to be at the origin of the eruptions deforming the icy shell by push-pull motions as the moon follows an elliptical path around the giant planet. But the energy produced by tidal friction in the ice, by itself, would be too weak to counterbalance the heat loss seen from the ocean; the globe would freeze within 30 million years. More than 10 GW of heat can be generated by tidal friction inside the rocky core. Water transport in the tidally heated permeable core results in hot narrow upwellings with temperatures exceeding 90 °C, characterized by powerful (1-5 GW) hotspots at the seafloor, particularly at the south pole. The release of heat in narrow regions favors intense interaction between water and rock, and the transport of hydrothermal products from the core to the plume sources (Choblet et al., 2017, Nature Astronomy, doi:10.1038/s41550-017-0289-8)
In Gk. mythology Enceladus was a Titan who battled Athene in their war against the gods. When he fled the battlefield, Athene crushed him beneath the Sicilian Mount Etna.
Enkelâdos, from the original Gk. pronunciation of the name.
Fr.: division de Encke
A region of decreased brightness within the A ring of Saturn.
In honor of Johann Franz Encke, → Encke's comet. Gap, from O.N. gap "chasm," related to gapa "to gape."
Gâf, variant kâf "split, slit," stem of kâftan, kâvidan "to split; to dig," Mid./Mod.Pers. škâf- škâftan "to split, burst," Proto-Iranian *kap-, *kaf- "to split;" cf. Gk. skaptein "to dig;" L. scabere "to scratch, scrape," P.Gmc. *skabanan (Goth. skaban; Ger. schaben; E. shave). PIE base *(s)kep- "to cut, to scrape, to hack."
donbâledâr-e Enké (#)
Fr.: comète de Encke
A faint comet with the shortest known period (about 3.30 years). Its semimajor axis is 2.21 AU and aphelion 4.1 AU. it is the parent body of the Taurids meteor shower. The comet was first observed in 1786 by the French astronomer Pierre Méchain.
Named after the German astronomer Johann Franz Encke (1791-1865), who in 1819 computed its orbit and proved that sightings of apparently different comets in 1786, 1795, 1805, and 1818 were in fact appearances of the same comet. → comet.
ramzândan, ramz gozâštan
From en- "in; into" + → code.
An electronic device or software program used to convert (a message, information, data) into a specialized digital format for efficient transmission or transfer.
ramzâneš, ramz gozâri
A meeting, especially one that is unplanned, unexpected, or brief. An often violent
meeting; a clash.
From O.Fr. encountrer "confront," from encontre "against, counter to," from L.L. incontra "in front of," from L. in- "in" + contra "against."
Ruyâruyi "being face to face," from ru, ruy "face, countenance," variant rox (Mid.Pers. rôy, rôdh "face," Av. raoδa- "growth," in plural "appearance," from raod- "to grow, sprout, shoot," cf. Skt. róha- "rising, height") + euphonic interfix -â- + ruy + noun suffix -i.
From en- "in; into" + L. crypt, from Gk. kryptos "hidden, concealed, secret" + → -tion.
Darnahândan, from dar-, → in- + nahândan "to hide, conceal," from nahân "concealed, hid; clandestine;" Mid.Pers. nihân "secrecy, a secret place, a hiding place," nihânik "concealed;" Av. niδāti- "deposing, deposit."
A process that transforms data into another format in such a way that only specific individual(s) can reverse the transformation. Encryption is for maintaining data confidentiality. See also → decryption and → encoding.
From Fr., from Gk. endon "in, within, at home," from en "in" + -don, base of domos "house," → domain.
Darun "in, into, within;" Mid.Pers. andarôn "inside," from andar, → inter- + rôn "side, direction;" Av. ravan- "(course of a) river."
Fr.: processus endoénergétique
A nuclear or molecular process in which some of the energy of the incoming particle is absorbed by, or transferred to, the other particle.
→ endo- + -ergic, a combining form with the meanings "activated by, sensitive to, releasing, resembling the effect produced by the substance or phenomenon specified by the initial element," from → erg, → energy + → -ic; → process.
Farâravand, → process; kâružgir, from kâruž, → energy, + gir present stem of gereftan "to take, seize, catch" (Mid.Pers. griftan, Av./O.Pers. grab- "to take, seize," cf. Skt. grah-, grabh- "to seize, take," graha "seizing, holding, perceiving," M.L.G. grabben "to grab," from P.Gmc. *grab, E. grab "to take or grasp suddenly;" PIE base *ghrebh- "to seize").
farâravand-e garmâgir (#)
Fr.: processus endothermique
Process during which heat is absorbed by the system from outside.
From garmâ "heat, warmth" (Mid.Pers. garm, O.Pers./Av. garəma- "hot, warm," cf. Skt. gharmah "heat," Gk. thermos "warm," L. formus "warm," P.Gmc. *warmaz, O.E. wearm, O.H.G., Ger. warm, PIE *ghworm-/*ghwerm-, as above) + gir present tense stem of gereftan "to take, seize, catch" (Mid.Pers. griftan, Av./O.Pers. grab- "to take, seize," cf. Skt. grah-, grabh- "to seize, take," graha "seizing, holding, perceiving," M.L.G. grabben "to grab," from P.Gmc. *grab, E. grab "to take or grasp suddenly;" PIE base *ghrebh- "to seize").
1) kâružmand; 2) kâruži
Fr.: 1) de grande énergie, énergique; 2) énergétique
1) Having a relatively high amount of energy.
energetic solar particles
zarrehâ-ye xoršidi-ye kâružmand
Fr.: particules solaires énergétiques
Electrons and atomic nuclei ejected by solar flares, travelling with velocities amounting to a fraction of the velocity of light, and energies mostly in the range 1-100 million → electronvolts (eV), but occasionally as high as 15 billion eVs. Also known as solar → cosmic rays.