An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A movement or action to accomplish a change of position.

From Fr. manoeuvre "manipulation, maneuver," from O.Fr. manovre "manual work," from M.L. manuopera, from manuoperare "work with the hands," from L. manu operari, from manu ablative of manus "hand" + operari "to work," → operate.

Metallic chemical element; symbol Mn. Atomic number 25; atomic weight 54.938; melting point about 1,244°C; boiling point about 1,962°C.

The name derives from the Latin magnes for "magnet" since pyrolusite (MnO₂) has magnetic properties. It was discovered by the Swedish pharmacist and chemist Carl-Wilhelm Scheele in 1774.

Manganez, loan from Fr.

1) Readily perceived by the eye or the understanding; evident; obvious; apparent; plain.
2) To make clear or evident to the eye or the understanding; show plainly (Dictionary.com).

M.E., from O.Fr. manifest "evident, palpable," or from L. manifestus "plainly apprehensible, clear, apparent, evident;" "proved by direct evidence;" "caught in the act," probably from manus "hand," + -festus "struck; (able to be) seized."

From Torbat-Heydariye-yi nemusâr "evident, conspicuous, visible," from nemu-, nemudan "to show, display" from Mid.Pers. nimūdan, from ne- "down; into;" O.Pers./Av. ni- "down; below; into," → ni-, + mu- (as in âz-mu-dan, â-mu-dan, far-mu-dan, pey-mu-dan, etc.); Av. mā(y)- "to measure," → display, + -sâr a suffix of state, position, similarity.

1) An act of manifesting.
2) The state of being manifested.
3) Outward or perceptible indication; materialization.
4. A public demonstration, as for political effect (Dictionary.com).

Verbal noun of → manifest; → -tion.

A → topological space in which every point has a → neighborhood which resembles → Euclidean space (Rⁿ), but in which the global structure may be different. An example of a one-dimensional manifold would be a circle; if you zoom around a point the circle looks locally like a line (R¹). An example of a two-dimensional manifold would be a sphere; a small portion looks locally like a plane (R²). See also → flat manifold.

O.E. monigfald (Anglian), manigfeald (W.Saxon) "varied in appearance," from manig "many" + -feald "fold."

Baslâ, 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") + lâ "fold."

The fractional or the decimal part of a → common logarithm. For example, log₁₀ 4000 = 3.602, where the → characteristic is 3 and the mantissa 0.602.

From L. mantis "makeweight, addition," of unknown origin. Introduced by Henry Briggs (1561-1630).

→ makeweight.

1) General: Something that covers, envelops, or conceals. → grain mantle; → plasma mantle.
2) Geology: → Earth's mantle.

O.E. mentel "loose, sleeveless cloak," from L. mantellum "cloak," perhaps from a Celtic source.

1) Rupuš "over-garment, cloak," from ru "surface, face; aspect; appearance" (Mid.Pers. rôy, rôdh "face;" Av. raoδa- "growth," in plural form "appearance," from raod- "to grow, sprout, shoot;" cf. Skt. róha- "rising, height") + puš "covering, mantle," from pušidan "to cover; to put on" (Mid.Pers. pôšidan, pôš- "to cover; to wear;" cf. Mid.Pers. pôst; Mod.Pers. pust "skin, hide;" O.Pers. pavastā- "thin clay envelope used to protect unbaked clay tablets;" Skt. pavásta- "cover," Proto-Indo-Iranian *pauastā- "cloth").
2) Gušté, from gušt "flesh, meat, pulp of fruit;" Mid.Pers. gôšt "meat;" Av. gah- "to eat;" cf. Skt. ghas- "to eat, devour," ghásati "eats" + nuance suffix -é.

The mathematical problem of solving the equations of motions of any number of bodies which interact gravitationally. More specifically, to find their positions and velocities at any point in the future or the past, given their present positions, masses, and velocities.

Many, from M.E. mani, meni, O.E. monig, manig; → body; → problem.

The distribution law for kinetic energies (or, equivalently, speeds) of molecules of an ideal gas in equilibrium at a given temperature.

→ maxwell; → Boltzmann's constant; → distribution.

In → iron meteorites, any of very fine parallel lines that cross each other at various angles. They can be seen after cutting diagonally across the sample.

Named after Johann G. Neumann, who discovered them in 1848 in the iron meteorite Braunau, which fell in 1847; → line.

The moving of a spacecraft between two different orbits resulting from a change in its velocity (acceleration). Generally, manoeuvres are caused by → thrust from the spacecraft's motors.

→ orbital; → maneuver.

→ orbital maneuver.

→ orbital; → manoeuvre.

1) The act of performing a ceremony, play, piece of music, etc.
2) The execution or accomplishment of work, acts, feats, etc.
3) A musical, dramatic, or other entertainment presented before an audience (Dictionary.com).

→ perform; → -ance.

Lasting or remaining without essential change.

Permanent, from M.Fr. permanent, from L. permanentem "remaining," pr.p. of permanere "endure, continue, stay to the end," from per- "through" + manere "stay," cognate with Pers. mândan, as below; → gas.

Gas which cannot be liquefied by pressure alone; gas above its critical temperature.

→ permanent; → gas.

A piece of magnetic material which, having been → magnetized, retains a substantial proportion of its → magnetization indefinitely. In permanent magnets the magnetic field is generated by the internal structure of the material itself. Atoms and crystals constituting materials are made up of electrons and atomic nuclei. Both the nucleus and the electrons themselves act like little magnets. There is also a magnetic field generated by the orbits of the electrons as they move about the nucleus. So the magnetic fields of permanent magnets are the sums of the nuclear spins, the electron spins and the orbits of the electrons themselves. In many materials, the magnetic fields are pointing in all sorts of random directions and cancel each other out and there is no permanent magnetism. But in certain materials, called → ferromagnets, all the spins and the orbits of the electrons will line up, causing the materials to become magnetic. Many permanent magnets are created by exposing the magnetic material to a very strong external magnetic field. Once the external magnetic field is removed, the treated magnetic material is now converted into a permanent magnet. Overheating a permanent magnet causes the magnet's atoms to vibrate violently and disrupt the alignment of the atomic domains and their dipoles. Once cooled, the domains will not realign as before on their own and will structurally become a temporary magnet (MagLab Dictionary).

→ permanent; → magnet.

Storage capacity which does not depend on a continuous supply of power, e.g. disks, magnetic tapes, etc.

→ permanent; → memory.

(Geophysics): A layer of plasma located on the night-side of Earth, inside the magnetosphere and along its boundary. Under the action of electromagnetic forces, plasma contained in the mantle drifts equator-ward, along the tail axis.

→ plasma; → mantle.

A person who is responsible for directing and controlling the work and staff of a project.

→ project; → manager.

A space with an affine connection (without torsion), at each point of which the tangent space is a → pseudo-Euclidean space (Encyclopedia of Mathematics, Kluwer Academic Publications, Editor in chief I. M. Vinogradov, 1991).

→ pseudo-; → Riemannian; → space.