A unit of angular measurement equal to one sixtieth of a degree.
From O.Fr. minut, from M.L. minuta "minute, short note," from L. minuta, feminin of minutus "small, minute." In M.L., pars minuta prima "first small part" was used by Ptolemy for "one-sixtieth of a circle," later of an hour (next in order was secunda minuta, which became second).
Daqiqé, loan from Ar. daqiqat.
A → red giant → variable star in the constellation → Cetus, called also Omicron (ο) Ceti. Its → visual magnitude varies between 2.0 and 10.1 over a period of about 330 days, and its → spectral type between M5 and M9. Its diameter is 400-500 times that of the Sun, and it lies approximately 420 → light-years away. Mira is a → binary star, consisting of the red giant Mira A along with Mira B. It is the prototype of a class known as → long-period variables, or → Mira variables.
From L. mira "wonderful," as named by J. Hevelius (1611-1687).
Fr.: variables de type Mira
A variant of → Merak.
Fr.: fantôme de Mirach
Same as → NGC 404.
An optical phenomenon caused by → refraction of light in the lowest layers of the Earth's → atmosphere especially in the → desert, over a hot pavement, or at → sea. Due to temperature variations, the air → density varies, leading to a spatial variation of the → index of refraction of → air. As a result, light from a single point takes more than one path to the observer and the → image of some distant object appears displaced from its true position; the image may appear distorted, inverted, or wavering.
From Fr. mirage, from (se) mir(er) "to look at (oneself), be reflected" (from L. mirare "to wonder at, admire") + suffix -age.
Sarâb "mirage," literally "water point, water origin, water head," probably from sar "origin, beginning," → head, + âb, → water. The similarity with Ar. serab (cf. Hebrew sharab "burning heat, parched ground") may be fortuitous.
The eleventh of Uranus's known satellites and the innermost of Uranus' large moons. Its is about 470 km in diameter and orbits Uranus at about 130,000 km from its planet. It was discovered by Kuiper in 1948.
Miranda is a daughter of the magician Prospero in Shakespeare's The Tempest.
Mirfak (α Persei)
The brightest star of Perseus, with a visual magnitude of 1.8. It is a giant of spectral type F5 lying some 590 light-years away.
From Ar. al-Mirfaq (
Merfaq, from Ar. al-Mirfaq, as above.
A smooth, highly polished surface, for reflecting light, that may be plane or curved. The actual reflecting surface is usually a thin coating of silver or aluminum on glass.
From O.Fr. mireor "a reflecting glass," earlier miradoir, from mirer "look at," from V.L. *mirare, from L. mirari "to wonder at, admire."
Âyené, from Mid.Pers. êwênag "mirror," from *âdênak, from Proto-Iranian *ādayanaka-, from prefix ā- + the root of Av. dā(y)- "to see," didāti "sees" (cf. Mod.Pers. didan "to see," Mid.Pers. ditan "to see, regard, catch sight of, contemplate, experience;" O.Pers. dī- "to see;" Skt. dhī- "to perceive, think, ponder; thought, reflection, meditation," dādhye; Gk. dedorka "have seen") + suffix -ak.
Fr.: disque miroir
The material on which the reflecting coating is applied. It may be glass, quartz, or metal.
→ mirror; blank "a piece of metal ready to be drawn, pressed, or machined into a finished object," from M.E., from O.Fr. blanc (adj.) from Gmc; cf. O.E. blanca "white horse," O.H.G. blanch "bright, white."
Fr.: ébauche de miroir
Same as → mirror blank.
âzmun-e âyené (#)
Fr.: test d'un miroir
The observation and measurement of the flatness of a mirror surface. The process generally is done before coating so as not to damage the delicate coated surface. For coated and curved surfaces, non-contact methods are often employed, generally using interference techniques.
Mirzam (β Canis Majoris)
The fourth brightest star in the constellation → Canis Major. It is a B1 → giant of magnitude 2.0 lying about 500 → light-years away. Mirzam is one of the brightest of the → Beta Cephei variable stars.
From Ar. al-Mirzam (
From mis- a prefix meaning "ill, mistaken, wrong, wrongly" + → alignment.
Fr.: manquer, rater, louper
1) Fail to hit, reach, or come into contact with (something aimed at);
to fail to do something.
M.E. missen, O.E. missan "fail to hit, miss (a mark); fail in what was aimed at," akin to Du. missen, Ger. missen "to miss, fail," from PIE *mei- "to change, go, move."
Napidan, literally "do not attain, reach, or find," from negation suffix na-, → not, + Av. ap- "to reach, attain;" cf. Mid./Mod.Pers. (+abi-) yâftan "to obtain, to find;" Proto-Ir. *Hap/f- "to reach, attain;" PIE *H1ep- "to take, seize, grab;" cf. L. apiscor "to reach, to get" (Cheung 2007).
An object or weapon for throwing, hurling, or shooting. → ballistic missile.
From Fr. missile, from L. missile "weapon that can be thrown," from missus, p.p. of mittere "to send."
Mušak, literally "little mouse," or "mouse like," from a firework explosive that was likened to a mouse, from muš, → mouse, + -ak diminutive or similarity suffix.
jerm-e gomšodé (#)
Fr.: masse manquante
The unseen mass whose gravitational influence is needed to account for the way galaxies rotate, and also to bind clusters of galaxies together. It is thought to consist, in part, of giant halos of dark matter that surround the visible portions of galaxies, and similar material that invisibly occupies the intergalactic voids. Same as → hidden mass; → dark matter.
Missing, from miss "to fail to be present," from M.E. missen, O.E. missan; cf. O.Fris. missa, M.Du. missen, Ger. missen "to miss, fail;" → mass.
Jerm, → mass; gomšodé "lost, missing," from gom "missing, lost" + šodé p.p. of šodan "to become" (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").
missing satellites problem (MSP)
parâse-ye bandevârhâ-ye gomšodé
Fr.: problème des satellites manquants
The observed underabundance, by one or two orders of magnitude, of → dwarf galaxies orbiting → spiral galaxies compared to their number predicted by the standard model. The → cold dark matter (CDM) model predicts that dwarf galaxies are the building blocks of large galaxies like the Milky Way and should largely outnumber them. Dwarf galaxies form first, they merge into bigger and bigger galaxies, and galaxies into groups of galaxies. The dark matter halos, however, are very dense, and dwarf halos are not destroyed in the merging, resulting in their large predicted number, in numerical simulations.
An operation designed to carry out the goals of a specific program, such as a a space flight or voyage.
Mission, from L. missionem (nominative missio) "act of sending," from mittere "to send," of unknown origin.
Gosilân, from gosil, variant gosi "sending away, dismission;" Mid.Pers. wisé "to despatch" (Parthian Mid.Pers. wsys- "to despatch;" Buddhist Mid.Pers. wsydy "to despatch;" Sogdian 'ns'yd- "to exhort"), from Proto-Iranian *vi-sid- "to despatch, send off," from prefix vi- "apart, away, out," + *sid- "to call" + -ân nuance suffix.
A very thin fog consisting of an aggregate of microscopic water droplets or wet hygroscopic particles (of diameter not less than 0.5 mm), in which the visibility at the earth's surface is greater than 1 km.
O.E. mist "dimness, mist," from P.Gmc. *mikhstaz (cf. M.L.G. mist, Icelandic mistur), from PIE *migh-/*meigh-; cf. Pers. miq "fog, mist;" Gk. omikhle, O.C.S. migla, Skt. megha- "cloud, mist." → nebula.
Nezm "mist, fog," variants nezu, nezvâ "mist," nam "moisture, humidity;" Av. napta- "moist," nabās-câ- "cloud," nabah- "sky;" cf. Skt. nábhas- "moisture, cloud, mist;" Gk. nephos "cloud, mass of clouds," nephele "cloud;" L. nebula "mist," nimbus "rainstorm, rain cloud;" O.H.G. nebul; Ger. Nebel "fog;" O.E. nifol "dark;" from PIE *nebh- "cloud, vapor, fog, moist, sky."