Fr.: cycles de Milankovitch
The theory according to which variations in the elements of Earth-Sun geometry are responsible for the sequence of ice ages during the Pleistocene era. The main elements are the varying tilt of the Earth's rotational axis, and the varying eccentricity of the Earth's orbit.
Named after the Serbian mathematician Milutin Milankovitch (1879-1958), who introduced the concept during the first half of the twentieth century.
An opaque white fluid secreted by female mammals for the nourishment of their young.
M.E.; O.E. meol(o)c, (Anglian) milc; cf. Gr. Milch, Goth. miluks; akin to L. mulgere, Gk amelgein "to milk;" PIE base *melg- "wiping, stroking;"
Šir "milk;" Mid.Pers. šir; (Parth. šyft); Khotanese švida; Sogd. xšiβd (Yaghnobi xšift; Yadgha xšira); Av. xšvid-, xšvipta-; cf. Skt. ksira- "milk."
Râh-e Širi (#)
Fr.: Voie lactée
The diffuse glowing band of light seen on dark nights spanning the sky as a great circle. It is produced by light from stars and nebulae in the → Galactic plane. The apparent form of the Milky Way in the sky results from a geometrical effect created by our location in the outlying regions of a huge, flattened disk of stars. → Milky Way galaxy.
From L.L. galaxias "Milky Way," from Gk. galaxis kyklos
"emilky circle," from gala (gen. galaktos) "milk."
Râh, → way; širi, adj. of šir "milk;" Mid.Pers. šir; cf. Skt. ksira- "milk."
Milky Way galaxy
kahkešân-e râh-e širi (#)
Fr.: Voie lactée
A → spiral galaxy, of which the
→ solar system is a small part.
It is the second largest in our → Local Group of galaxies.
The Milky Way is a disk-shaped system,
with a diameter of between 80,000 and 100,000 → light-years
and a thickness of about 2,000 light-years, containing more than
1011 stars. The stars are divided into two main categories,
→ Population II stars and
→ Population I stars.
Milky Way system
râžmân-e râh-e širi
Fr.: Voie lactée
The huge star system of which the Sun is a member. Same as the Galaxy or the Milky Way galaxy.
Fr.: expérience de Miller-Urey
A chemical experiment conducted in 1953 that aimed at checking Alexander Oparin's and J. B. S. Haldane's hypothesis that under putative conditions present in the atmosphere of the early Earth inorganic molecules would spontaneously form organic molecules. Miller and Urey filled a sterile flask with a mixture of water, ammonia, methane, and hydrogen. The mixture was heated to evaporate water to produce water vapor. High-voltage electric sparks were passed through the mixture to simulate lightning. After a week, contents were analyzed. Amino acids, the building blocks for proteins, were found.
Named after Stanley L. Miller (1930-2007) and Harold C. Urey (1893-1981); → experiment.
Prefix meaning one thousandth (10-3).
From Fr., from L. mille "thiusand."
Mili-, loan from Fr.
One thousandth of a bar; a unit of atmospheric pressure. The average atmospheric pressure at sea level is 1.01325 bars or 1013.25 mb.
Millikan's oil-drop experiment
âzmâyeš-e Millikan (#)
Fr.: expérience de Millikan
A precision experiment for measuring the → electron charge. By studying the falling speed of small charged droplets in the gravitational field of the Earth subjected to an adjustable electric field, Millikan (1909) was able to demonstrate conclusively the discrete nature of electric charge, and moreover measure the charge of an individual electron.
Robert Andrews Millikan (1868-1953); → experiment.
mowj-e milimetri (#)
Fr.: onde millimétrique
Microwaves with wavelengths between 1 and 10 millimeter, corresponding to frequencies between 300 GHz to 30 GHz. → millimeter-wave astronomy.
axtaršenâsi-ye mowjhâ-ye milimetri (#)
Fr.: astronomie millimétrique
That part of radio astronomy which uses electromagnetic waves in the range 1-10 millimeter to study various components of the Universe, in particular the chemistry of interstellar matter.
A thousand thousand (106).
O.Fr. million, from It. millione, literally "a great thousand," augmentative of mille "thousand," from L. mille.
Milyon, Loan from Fr.
pulsâr-e milisâniyé (#), tapâr-e ~ (#)
Fr.: pulsar milliseconde
A type of pulsar that spins around its axis every few thousands of a second. The prototype 1937+21, discovered in 1982, has a period of 1.56 milliseconds; i.e. it spins more than 600 times per second, the fastest so far found (Backer et al. 1982, Nature 300, 615). These pulsars are distinguished from typical pulsars by the extreme stability of their rotation period. It is thought that they have been rejuvenated by a "spin-up process" involving the accumulation of matter from a companion star. → recycled pulsar.
One thousands of a → sievert.
Fr.: croix de Mills
Named after the Australian engineer and astronomer Bernard Yarnton Mills (1920-2011; see R.H. Frater et al. 2013, arXiv:1306.6371); → cross.
Milne cosmological model
model-e keyhânšenâxti-ye Milne (#)
Fr.: modèle cosmologique de Milne
Same as → Milne Universe.
Giti-ye Milne (#)
Fr.: Univers de Milne
A model of the → Universe which is devoid of matter and where the → space-time is → open (ΩM = 0, ΩR = 0, ΩΛ = 0, k = -1). The Universe will expand at a constant rate for ever. See also → empty Universe, → de Sitter Universe.
Fr.: approximation de Milne-Eddington
The approximation of a stellar atmosphere with a plane parallel grey atmosphere in radiative equilibrium. It is assumed that a spectral is formed in such a way that the ratio of the line absorption coefficient to the continuous absorption coefficient is constant with depth.
The seventh of Saturn's known satellites. It is 392 km in diameter and orbits Saturn at a mean distance of 185,520 km. Mimas' low density (1.17) indicates that it is composed mostly of water ice with only a small amount of rock. The surface is saturated with impact craters, dominated by the largest one measuring 130 km across, known as Herschel. Mimas was discovered in 1789 by Herschel.
In Gk. mythology, Mimas was one of the Gigantes slain by Hephaestus, the god of fire, volcanism, smiths and craftsmen, with barrage of red-hot metal.
Fr.: esprit, intelligence, raison
1) The human faculty to which are ascribed thought, feeling, etc; often regarded as an
immaterial part of a person (Dictionary.com).
M.E. mynd(e), from O.E. gemynd "memory, remembrance; thought, purpose" (cf. Gothic muns "thought," munan "to think;" ON minni "mind;" Ger. Minne (archaic) "love," originally "memory"), from PIE root *men- "think, remember;" cf. Pers. mân, man "mind, thought;" Av. man- "to think;" Skt. matih "thought," Gk. mania "madness," mentio "remembrance;" Lith. mintis "thought, idea," O.C.S. mineti "to believe, think," Russ. pamjat "memory."
Ment, from Mid.Pers. mênitan "to think," Av. mainyeite "he thinks;" O.Pers. man- "to think," maniyaiy "I think," Ardumaniš- (proper noun) "upright-minded," Haxāmaniš- (proper noun, Hellenized Achaemenes, founder of the Achaemenian dynasty) "having the mind of a friend;" Av. mân- "to think," manah- "mind, thinking, thought; purpose, intention," mainyu- "mind, mentality, mental force, inspiration," cf. Sogdian mân "mind;" Skt. man- "to think," mánye "I think," manyate "he thinks," mánas- "intelligence, understanding, conscience;" Gk. mainomai "to be angry," mania "madness," mantis "one who divines, prophet;" L. mens "mind, understanding, reason," memini "I remember," mentio "remembrance;" Lith. mintis "thought, idea;" Goth. muns "thought," munan "to think;" Ger. Minne "love," originally "loving memory;" O.E. gemynd "memory, thinking, intention;" PIE base *men- "to think, mind; spiritual activity."