Fr.: référentiel en mouvement
Fr.: groupe mobile
A young → stellar population that shares a common space motion. A moving group remains kinematically distinct within the general field stars at ages < 1 billion years, before being dispersed. As progenitor gas is cleared by OB star winds, and the natal cluster expands, stars with sufficiently high velocities become unbound and form a young, coeval moving group, possibly leaving behind a bound open cluster. Because of their common origin, moving group members have a shared age and composition. The nearest moving group is the → TW Hydrae association.
MRN dust model
Fr.: modèle MRN
A model concerned with the distribution in size of → interstellar grains to account for observations of → interstellar extinction from 0.11 μm to 1.0 μm. The → distribution has the form N(a)da ∝ a-3.5da, where a is the grain radius. It extends from 5 nm to 1 μm for → graphite and over a narrower range for other materials.
Fr.: μ Cephei
A → red supergiant star in the → constellation → Cepheus. It is one of the largest and most luminous stars known in the → Milky Way. μ Cephei appears garnet red and is given the → spectral type of M2 Ia. The star may even be the largest star visible to the → naked eye with an estimated radius of 1.15 billion kilometres. If it replaced the Sun, it would extend beyond the orbit of Saturn. Some of its → physical parameters are: mass = 15 Msol; → radius = 1650 Rsol; → luminosity = 60 x 104 Lsol; → effective temperature = 3690 K. Also called Herschel's → Garnet star.
Cephei, genitive of → Cepheus.
The → sterile offspring of a female horse and a male donkey.
M.E., from O.E. mul, from O.Fr. mul "mule, hinny," from L. mulus "a mule," probably from a pre-Latin Mediterranean language.
Astar, from Mid.Pers. astar, ultimately from *asa-tara-, literally "horse related," from *asa- variant of aspa-, → horse, + -tara- a suffix of relation and comparative adjectives; cf. Skt. asvátara- "mule."
A combining form meaning "many, much, multiple, many times, more than one, more than two, composed of many like parts, in many respects."
From L. multus "much, many," from PIE base *mel- "strong, great, numerous;" cf. L. melior "better," Gk. mala "very, very much."
Bas-, from bas "many, much;" Mid.Pers. vas "many, much;" O.Pers. vasiy "at will, greatly, utterly;" Av. varəmi "I wish," vasô, vasə "at one's pleasure or will," from vas- "to will, desire, wish."
Fr.: spectroscopie multi-objets
A technique of spectroscopy using fiber optics whereby several objects distributed over the field of view can be observed simultaneously.
Of an approach or study that juxtaposes disciplinary perspectives, adding breadth and available knowledge, information, and methods. The involved disciplines speak as separate voices in encyclopedic alignment. The status quo is not interrogated, and disciplinary elements retain their original identity. See also → interdisciplinary and → transdisciplinary (Thompson Klein, J. 2010, Creating Interdisciplinary Campus Culture, John Wiley and Sons, Inc.).
Fr.: système multi-planète
A stellar system with more than one orbiting planet.
Consisting of, having, or involving several or many individuals, parts, elements, etc.
From Fr. multiple, from L.L. multiplus "manifold," from L. → multi- "many, much" + -plus "fold," from base of plicare "to fold, twist."
Bastâ-, from bas "many, much" (Mid.Pers. vas "many, much;" O.Pers. vasiy "at will, greatly, utterly;" Av. varəmi "I wish," vasô, vasə "at one's pleasure or will," from vas- "to will, desire, wish") + tâ "fold, plait, ply; piece, part," also a multiplicative suffix; Mid.Pers. tâg "piece, part."
Fr.: poses multiples
The division of a relatively long exposure into several successive shorter ones, e.g. to avoid detector saturation.
Fr.: intégrale multiple
A series of successive integrations in which the integral operator acts on the result of preceding integration.
Fr.: diffusion multiple
A process of → radiative transfer in which more than one → scattering event may be of importance before → transmission, → reflection, or → absorption. In → radiation-driven winds photon scattering can take place in different → spectral lines. Each scattering occurs in a different spectral line, and successive scatterings occur at lower energies (longer wavelength). The standard theory of line driving (→ CAK model) assumes that photons can be scattered only once in the wind, which is a reasonable assumption for normal → O stars. In → Wolf-Rayet stars, where photons evolve in an atmosphere with a strong → ionization stratification, multiple scattering is important. Indeed the strength of W-R winds appears to exceed the single scattering limit.
Fr.: étoile multiple
multiple star system
Fr.: système multiple
A stellar system composed of several stars bound together by gravitational attraction and revolving around a common center of mass.
Fr.: système multiple
A group of spectral lines arising from transitions having a common lower energy level.
From → multi- + -plet on the model of triplet.
Bastâyé, from bastâ-→ multi- + euphonic -yé, from -é nuance suffix.
A number to be multiplied by another.
From L. multiplicandum, from multiplicandus "to be multiplied," gerundive of multiplicare, → multiply.
Bastâšow, literally "that undergoes multiplication," from bastâ, → multiple, + šow, present stem and agent noun of šodan "to become, to be, to be doing, to go, to pass," from Mid.Pers. šudan, šaw- "to go;" Av. šiyav-, š(ii)auu- "to move, go," šiyavati "goes," šyaoθna- "activity; action; doing, working;" O.Pers. šiyav- "to go forth, set," ašiyavam "I set forth;" cf. Skt. cyu- "to move to and fro, shake about; to stir," cyávate "stirs himself, goes;" Gk. kinein "to move;" Goth. haitan "call, be called;" O.E. hatan "command, call;" PIE base *kei- "to move to and fro."
In general, the process of repeatedly adding a quantity to itself a certain number of times, or any other process which has the same result.
Verbal noun of → multiply.
Fr.: croix de multiplication
The sign used to indicate multiplication, either a times sign (×), a centered dot (·), or an asterisk. The multiplication sign was introduced by William Oughtred in 1631.