A diffraction grating placed over the aperture of a telescope in order to produce spectra of all the objects in the field of view.
Fr.: lentille de l'objectif
A dispersing prism placed in front of a telescope objective to produce spectra of all luminous objects in the field of view.
Fr.: probabilité objective
A probability determined by the long-term frequency of an event; in contrast to subjective probability.
From L. ob- "toward" + latus, abstracted from its opposite, prolatus "lengthened."
Pax "oblate," of unknown etymology.
Fr.: sphéroïde aplati
An ellipsoid produced by rotating an ellipse through 360° about its minor axis. Compare with → prolate spheroid.
The property possessed by a round body that is flattened at the poles.
Noun from → oblate.
1) farizidan; 2) farizidé
1a) To bind or oblige morally or legally.
Back-formation from → obligation.
1) Something by which a person is bound or obliged to do certain things,
and which arises out of a sense of duty or results from custom, law,
M.E. obligacioun, from O.Fr. obligacion "obligation, duty, responsibility," from L. obligationem "an engaging or pledging," literally "a binding," noun of action from p.p. stem of obligare "to bind, bind up, bandage," from → ob- "to" + ligare "to bind," from PIE root *leig- "to bind."
Fariz, from Mid.Pers. frêz "obligation; duty."
Required as a matter of obligation; mandatory; incumbent; compulsory.
Farizgun, from fariz, → duty, + -gun "manner, fashion."
Neither perpendicular nor horizontal; having the axis not perpendicular to the base; slanting; sloping.
From M.Fr. oblique, from L. obliquus "slanting, sidelong, indirect," from ob "against" + root of licinus "(of an ox whose corn tips are) bent upward," from PIE base *lei- "to bend, be movable."
Yekvar, literally "slantingn to a side," from yek-, → one, + var "side," variant bar "side; breadth; breast" (Mid.Pers. var "breast;" Av. vouru "wide, broad, extended" (vourucašāni- "looking far"), related to varah- "breast;" cf. Skt. urú- "wide, broad," úras- "breast;" Gk. eurus "wide, broad;" PIE base uer-, ueru-s"wide, broad").
oblique rotator model
model-e carxande-ye yekvar
Fr.: modèle de rotateur oblique
A stellar model in which the rotation axis is tilted relative to the magnetic dipole axis. As the star rotates, observable quantities (e.g. the line-of-sight component of the magnetic field, stellar brightness, emission lines) are modulated according to the rotational period. Such a model was first put forward by D. Stibbs (1950, MNRAS, 110, 395).
Fr.: choc oblique
Fr.: sphère oblique
The celestial sphere when the circles parallel to the equator are cut obliquely by the horizon plane, which divides them into two unequal parts. In other words, the sphere when its axis is oblique to the horizon of the place.
1) General: The quality or state of being oblique.
State noun of → oblique.
obliquity of the ecliptic
Fr.: obliquité de l'écliptique
The angle between the Earth's → equatorial plane and the → ecliptic. Its present value is 23°26'13.5'' (or 23.43708 degrees). The effects of → precession and → nutation cause it to change between extreme values of 22.1 and 24.5 degrees over a period of approximately 41,000 years. It is currently decreasing.
Elongated, usually from the square or circular form.
Late M.E. oblonge, from L. oblongus "rather long," from ob- a prefix meaning "toward, to, on, over, against" + longus, → long.
Derâzak, from derâz "long," → length + -ak suffix.
Fr.: étoile OBN
1) Opposition to the spread of knowledge; a policy of withholding
knowledge from the general public.
From Fr. obscurantisme (1819), from obscurant, from obscure, from L. obscurus "dark, dusky," figuratively "unknown; unintelligible," from ob- "over" + -scurus "covered," from PIE *(s)keu- "to cover, conceal;" → -ism.