Fr.: combinaison affine
A linear combination of vectors in which all the vector coefficients add up to one.
→ affine; → combination.
General: Successive change from one thing or state to
another and back again.
Alternation, noun from → alternate.
angle of inclination
Fr.: angle d'inclinaison
1) General: The angle between one plane and another, or
the angle formed by a reference axis and a given line.
→ angle; → inclination.
Fr.: rendez-vous, attribution
1) An appointment for a meeting.
Verbal noun of → assign.
Fr.: désignation des astéroïdes
1) For an asteroid whose orbit is precisely known, a number and optionally
a proper name, e.g. (7) Iris, (24101) Cassini, (99942) Apophis.
→ asteroid; → designation.
Fr.: inclinaison de l'axe
The angle at which a planet's axis of rotation is tilted, with respect to that of the planet's orbit.
→ axial; → inclination.
Fr.: designation de Bayer
A stellar designation system in which a specific star is identified by a Greek letter, followed by the genitive form of its hosting → constellation's Latin name. For example, Alpha Eridani, Delta Cephei, Lambda Bootis. The Greek alphabet has only 24 letters. In case a single constellation contained a larger number of stars, Bayer amended with Latin letters: upper case A, followed by lower case b through z (omitting j and v), for a total of another 24 letters. Bayer did not go beyond z, but later astronomers added more designations using both upper and lower case Latin letters, the upper case letters following the lower case ones in general. Examples include, for Vela: a Vel (Velorum), z Vel, A Vel, Q Vel; for Scorpius: d Sco (Scorpii), A Sco; for Leo: b Leo (Leonis), o Leo, A Leo, → c Orionis. Compare with the → Flamsteed designation.
First introduced by Johann Bayer (1572-1625) in his atlas Uranometria, published in 1603 at Augsburg, Germany; → designation.
The complement of → declination; the angular distance along a great circle from the celestial pole, i.e., 90° - declination.
Codeclination, from → co- + → declination.
Hamvâkil, from ham-, → co-, + vâkil, → declination.
1) General: The act of combining or the state of being combined.
Noun from → combine
Fr.: désignation des comètes
A → nomenclature system for naming
In early 1995, a new comet designation system was established by the
→ International Astronomical Union. The main rules
are as follows:
→ comet; → designation.
The act of condemning; the state of being condemned.
Verbal noun of → condemn.
The act or state of coordinating or of being coordinated.
Verbal noun of → coordinate.
Fr.: composé de coordination
A chemical compound in which a group of atoms or ions are attached by a coordination bond to a usually metallic central atom or ion.
→ coordination; → compound.
Fr.: réseau de coordination
Crystallography: The crystal structure of a → coordination compound.
→ coordination; → lattice.
Fr.: nombre de coordination
1) Crystallography: The
number of nearest neighbors of an atom or ion in a → crystal lattice.
A large coordination number indicates that the structure is more closely packed.
→ coordination; → number.
The act of culminating or the instant at which a celestial object reaches its highest altitude above the horizon by crossing the observer's meridian. → upper culmination; → lower culmination.
Verbal noun of → culminate.
Bâlest, from Mid.Pers. bâlist "culmination point of a star; highest, summit," from bâlây "high" + -ist superlative suffix, Av. barəzišta- "highest," from barəz- "high, mount" (Skt. bhrant- "high," O.E. burg, burh "castle, fortified place," from P.Gmc. *burgs "fortress," Ger. Burg "castle," Goth. baurgs "city," E. burg, borough, Fr. bourgeois, bourgeoisie, faubourg; PIE base *bhergh- "high") + -išta- superlative suffix (Skt. -istha-, Gk. -istos, O.H.G. -isto, -osto, O.E. -st, -est, -ost).
1) Angular distance (symbol δ) from the celestial equator. One of the coordinates,
with → right ascension, that defines
the position of a heavenly body in the equator system. Declination is measured positively
(+) north or negatively (-) south of the celestial equator from 0° to
Fr.: axe de déclinaison
The axis to which the telescope tube is fastened in an → equatorial mounting.
→ declination; → axis.
parhun-e vâkileš, dâyeré-ye ~
Fr.: cercle de déclinaison
For a telescope with an → equatorial mounting, a graduated circle attached to the → declination axis that shows the → declination to which the telescope is pointing.
→ declination; → circle.
Fr.: groupe, catégorie, unité; dénomination
1) A name or designation.
Verbal noun of → denominate.