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

A device that imparts motion through reaction.

From L. motor "mover," from movere "to move."

Motor, loanword from Fr. moteur, as above.

A general term for a relatively bright or dark feature seen in monochromatic images taken in the red Hα → Balmer line of the solar → chromosphere. Mottles constitute the fine structure of the quiet solar chromosphere and are found near bright points at → supergranulation boundaries.

Probably back formation from motley, from M.E., O.E. mot "speck," of unknown origin; maybe related to Du. mot "sawdust, grit;" Norw. mutt "speck."

Capârak noun from capâr "spotted, speckled, mottled" + -ak diminutive/similarity suffix.

An observatory situated on a mountain 1700 m above sea level near Pasadena, California. It was built in 1904 by American astronomer George Ellery Hale as a solar-observing station for the Yerkes Observatory, but it became an independent observatory funded by the Carnegie Institution of Washington. In 1908 a 60-inch (152-cm) reflector, then the largest in the world, was added for observations of stars and galaxies. Ten years later a 100-inch (254-cm) reflecting telescope was put into service. It was the most powerful telescope in the world until the construction of the Palomar 200-inch reflector in 1948. The 100-inch telescope's most important discovery was Edwin Hubble's determination of the distance to the Andromeda Nebula in 1924. He showed that the nebula lay beyond the bounds of the Milky Way Galaxy and hence was a galaxy in its own right. Then in 1929, following the work of Vesto Slipher, Hubble and his assistant Milton Humason demonstrated that galaxies were moving away from one another. This movement is the expansion of the Universe.

→ mountain; a peak of the San Gabriel Mountains, located in northern Los Angeles County, California, named after Benjamin D. Wilson (1811-1878) a California statesman and politician; → observatory .

A natural elevation of the Earth's surface rising to a summit, and attaining an altitude greater than that of a hill.

From O.Fr. montaigne, from V.L. *montanea "mountain, mountain region," from L. montanus "mountainous," from mons (gen. montis) "mountain," minere "to project, jut, threaten," from PIE base *men- "to project;" cf. Av. matay-, mati- "protrusion of mountain range," framanyente "to be protruding, jutting;" from PIE base *men- "to stand out, to project;" (other related terms: mouth, prominent, amount, etc.).

Kuh "mountain," from Mid.Pers. kôf "mountain, hill; hump;" O.Pers. kaufa- "mountain;" Av. kaofa- "mountain."

Climate of relatively high elevations, specifically where optical observatories are situated.

→ mountain; → climate.

The support structure for a telescope that bears the weight of the telescope and allows it to be pointed at a target.

From verb mount, from O.Fr. monter "to go up, climb, mount," from V.L. *montare, from L. mons (genitive montis) → mountain

Barnešând, noun of Barnešândan "to set, to fix, make sit," from bar- "on, upon, up" (Mid.Pers. abar; O.Pers. upariy "above; over, upon, according to;" Av. upairi "above, over," upairi.zəma- "located above the earth;" cf. Gk. hyper- "over, above;" L. super-; O.H.G. ubir "over;" PIE base *uper "over") + nešândan "to place one thing upon another, to fix, insert," from nešastan "to sit;" Mid.Pers. nišastan "to sit;" O.Pers. nišādayam [1 sg.impf.caus.act.] "to sit down, to establish," hadiš- "abode;" Av. nišasiiā [1 sg.subj.acr.] "I shall sit down," from nihad- "to sit down," from ni- "down, below, into," → ni-, + had- "to sit;" PIE base *sed- "to sit;" cf. Skt. sad- "to sit," sidati "sits;" Gk. hezomai "to sit," hedra "seat, chair;" L. sedere "to sit;" O.Ir. suide "seat, sitting;" Welsh sedd "seat;" Lith. sedmi "to sit;" Rus. sad "garden;" Goth. sitan, Ger. sitzen; E. sit.

1) Any of numerous small Old World rodents of the family Muridae, especially of the genus Mus, introduced widely in other parts of the world.
2) Computers: A palm-sized, button-operated pointing device that can be used to move, select, activate, and change items on a computer screen (Dictionary.com).

M.E. mous (plural mis), from O.E. mus "small rodent;" cf. O.N., O.Fr., M.Du., Dan., Sw. mus, Du. muis, Ger. Maus, Pers. muš, as below.

Muš "mouse," dialectal Lori, Laki miš; Mid.Pers. mušk; cf. Skt. muš-, muš-; Gk. mys; L. mus; O.E. mys; Ger. Maus.

1) The body opening through which an animal takes in food.
2) This cavity regarded as the source of sounds and speech (TheFreeDictionary.com).

M.E., from O.E. muth "mouth, opening, door, gate;" cf. O.Sax., O.Norse munnr, Dan. mund, Du. mond, Ger. Mund.

Dahân "mouth," variant zafar "mouth;" Mid.Pers. dahân "mouth;" from *dafân the south-west form of Av. zafan, zafar "mouth;" cf. Skt. jambha- "set of teeth, mouth, jaws;" Ger. Kiefer "jaw."

Capable of being moved; not fixed in one place, position, or posture (Dictionary.com).

→ move; → -able.

1) To go from one place or position to another.
2) To change the position or location of something.

M.E. meven, moven; O.Fr. moveir; L. movere "move, set in motion;" Av. miuu- "to shove," as below.

Jonbidan "to move;" Lori, Laki jem "motion," Kurd. -žim- "to move, stir," žimây-/žimn- "to rock a cradle," Sogd. âyamb "to pervert, seduce, deceive," yâb "to wander, travel, rove;" Mid.Pers. jumbidan, jumb- "to move;" cf. Tocharian yâw-, yâp- "to enter;" Luwian /iba-/ "west;" PIE base *ieb^(h)- "to go, move inside" (Cheung 2007).
Miyâvidan, ultimately from Proto-Ir. *miHu- "to move;" cf. Av. auua.miuu- "to remove;" Khotanese mvīr- "to move;" Mid.Pers. pr-mws- "to be terrified;" Skt. mīv-/mu- "to move, remove, push;" L. movere, as above; PIE root *mieuH- "to set into motion" (Cheung 2007).

The act, process, or result of moving. A particular manner or style of moving.

→ move; → -ment.

In a state of movement. → moving cluster; → moving frame.

Verbal adj. of move, → motion.

A group of stars dynamically associated so that they have a common motion with respect to the local standard of rest.

→ moving; → cluster.

A → frame of reference that moves relative to the observer. The moving frame may be → inertial or → non-inertial. See also → rest frame.

→ moving; → frame.

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.

→ moving; → group.

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.

MNR, the initials of authors J. S. Mathis, W. Rumpl, and K. H. Nordsiek (1977, ApJ 217, 425), who introduced the mode; → dust; → model.

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."

A technique of spectroscopy using fiber optics whereby several objects distributed over the field of view can be observed simultaneously.

→ multi-; → object; → spectroscopy.