An Etymological Dictionary of Astronomy and Astrophysics

8 terms — E › E

E EA EB EC ED EF EG EH EI EJ EK EL EM EN EP EQ ER ES ET EU EV EW EX EY

E corona   تاج ِ E   tâj-e E Fr.: couronne E A part of the → solar corona defined by the → emission lines of hot gases. These emission lines include the so-called → forbidden lines of the strongly ionized atoms of iron, calcium, and other elements. The E corona is thinner than the → K corona and the → F corona (M.S.: SDE). See also: E indicating → emission; → corona.

E ring   حلقه‌ی ِ E   halqe-ye E Fr.: anneau E The → Saturn’s ring, with a width of 300,000 km, lying beyond the → G ring, at 180,000-480,000 km from the center of Saturn. See also: → ring.

E-ELT E-ELT Fr.: E-ELT The world’s largest → optical and → near infrared telescope, with a diameter of 42 m, to be built by the → European Southern Observatory (ESO). → First light is foreseen for 2018. The telescope has an innovative five-mirror design that includes advanced → adaptive optics to correct for the → atmospheric turbulence, giving exceptional → image quality. The → primary mirror will consist of almost 1000 hexagonal segments each 1.4 m across. The → secondary mirror will be 6 m in diameter. The E-ELT will collect 15 times more light than the largest optical telescopes operating today. On 26 April 2010, the ESO Council selected Cerro Armazones as the baseline site for the E-ELT. Cerro Armazones is a mountain at an altitude of 3060 m in the central part of Chile’s Atacama Desert, some 130 km south of the town of Antofagasta and about 20 km from Cerro Paranal, home of ESO → Very Large Telescope. See also: Short for the European Extremely Large Telescope

e-folding time   زمان ِ e-تایی   zamân-e e-tâyi Fr.: The time within which the amplitude of an oscillation increases or decreases by a factor e (= 2.71828…). Etymology (EN): From e the base of the natural, or Napierian, system of logarithms; folding, from -fold suffix meaning “of so many parts,” or denoting multiplication by the number indicated by the stem or word to which the suffix is attached (as in twofold; manifold), from O.E. -feald, related to Ger. -falt; Gk. altos, -plos, -plus; → time. Etymology (PE): Zamân, → time; e, as above; tâyi noun of tâ multiplicative suffix, also “fold, plait, wrinkle; like, resembling.”

e-mail   پَیِل   payel Fr.: mél, courriel A system for sending → messages from one individual to another via telecommunications links between → computers or → terminals using dedicated → software. A message sent by email (Dictionary.com). Etymology (EN): From electronic, → electronic, + mail, from M.E. male, from O.Fr. male “wallet, bag,” of Germanic source; cf. O.H.G. malaha “wallet, bag,” M.Du. male “bag;”) from PIE *molko- “skin, bag.” Etymology (PE): Payel, contraction of payâm-e elelktronik “electronic message,” from payâm, → message, elektronik, → electronic; cf. Fr. mél “e-mail,” from message + électronique, or courriel “e-mail,” from courrier + électronique.

E-mode polarization   قطبش ِ ترز ِ E   qotbeš-e tarz-e E Fr.: polarisation en mode E A → polarization component in the → cosmic microwave background radiation that depends only on → gradient, is independent of → curl and does not have → handedness. In contrast to the → B-mode, the E-mode may be due to both the → scalar perturbations and → tensor perturbations. See also: E, indicating electric-field like; → mode; → polarization.

e-term of aberration   بیراهش ِ ترم ِ e   birâheš-e tarm-e e Fr.: aberration elliptique The same as → elliptic aberration. See also: e, → elliptic; → term; → aberration.

E-type chondrite   کوندریت ِ گونه‌ی ِ E   kondrit-e gune-ye E Fr.: chondrite de type E Same as → enstatite chondrite. See also: → enstatite; → type; → chondrite.