Fourth planet from Sun and the seventh largest. Mass 6.42 × 1026 g (0.11 Earth's); radius 3397 km. Mean distance from Sun 1.52 A.U.. Sidereal period 687 days; synodic period 779.9 days. Surface temperature 248 K., rotational period 24h37m22s.6. Obliquity 23°59'. Atmosphere more than 90% CO2, traces of O2, CO, H2O. Two tiny satellites (Phobos and Deimos), both of which are locked in synchronous rotation with Mars.
Late M.E., from L. Mars the Roman god of war, Ares in Gk. mythology.
Bahrâm, from Mid.Pers. Vahrâm, from Vahrân "god of victory," from Av. vərəθraγna- "victory, breaking the defence, the god of victory." The first element vərəθra- "shield, defensive power," cf. Skt. vrtrá- "defence, name of a demon slain by Indra," Arm. vahagan name of a god (loanword from Iranian). The second element γna-, from Av., also O.Pers., jan-, gan- "to strike, hit, smite, kill" (jantar- "smiter"); cf. Mod.Pers. zadan, zan- "to strike, beat;" Mid.Pers. zatan, žatan; Skt. han- "to strike, beat" (hantar- "smiter, killer"); Gk. theinein "to strike," phonos "murder;" L. fendere "to strike, push;" Gmc. *gundjo "war, battle;" PIE *gwhen- "to strike, kill."
The → zero point of elevation on Mars. It is the elevation at which the atmosphere pressure is 6.1 millibars, or 610 → Pascals. Atmosphere pressure has to be used because Mars has no ocean, and "sea level" cannot be used like on Earth. More formally, the datum is a fourth-order, fourth-degree surface of equal → gravitational potential (determined from the Viking orbiter spacecraft) such that the pressure of the atmosphere is 6.1 millibars (source: Lunar and Planetary Institute, USRA).
Fr.: trojan de Mars
Fr.: tremblement de Mars
A quake on the → planet Mars, probably caused by some phenomena other than → tectonic plate motions. Unlike Earth, Mars seems to lack tectonic plates. Therefore, its quakes are thought to arise from the slow cooling of the planet over time, which causes the → crust to contract and develop fractures. These quakes can also come from the impact of → meteorites and possibly the movement of → magma deep below the surface. On April 6, 2019, the instrument called Seismic Experiment for Interior Structure (SEIS) on NASA's Mars → InSight Mission lander recorded quakes that appear to have come from inside the planet, the first time ever a likely marsquake.
Bahrâmi (#), Merixi (#)
Of, relating to, or like the planet → Mars.
M.E. marcien, from L. Marti(us) of, belonging to → Mars + -an a suffix of adjectives.
šaxâne-ye Bahrâmi, šahâbsang-e ~
Fr.: météorite martienne
A piece of rock that was ejected from the Martian surface into space by the impact of an asteroid or comet, and landed on Earth. So far about 100 Martian meteorites have been collected. These meteorites have elemental and isotopic compositions that match those of the Martian crust as measured by NASA's Mars exploration missions.
Fr.: plume de Mars
A slender, cloudy projection sometimes seen to extend from the surface of → Mars to very high altitudes. Noted and confirmed by amateur astronomers on photos of Mars in March 2012, possibly similar plumes have been found on archived images as far back as 1997. The plumes reach 200 km up, which seems too high for them to be related to wind-blown surface dust. Since one plume lasted for more than 10 days, it seemed too long lasting to be related to → aurora. The origin of this phenomenon is not yet known.
1) Having qualities appropriate to or usually associated with a man.
M.E. masculin, from O.Fr. masculin "of the male sex," from L. masculinus "male, of masculine gender," from masculus "male, masculine; worthy of a man," diminutive of mas "male person, male," of unknown origin.
Narin, from nar, → male.
1) A source of very intense, narrow-band, coherent microwave
radiation involving → stimulated emission, as
in the → laser.
Maser stands for Microwave Amplification by Stimulated Emission of Radiation; → laser.
gosil-e meyzeri (#)
Fr.: émission maser
An emission arising from the → maser process.
1) mâsk (#); 2) mâsk zadan (#)
Fr.: 1) masque; 2) masquer
1) Something that serves to cover or conceal.
From M.Fr. masque "covering to hide or guard the face," from It. maschera, from M.L. masca "mask, specter, nightmare," of uncertain origin.
1) Mâsk, loan from Fr., as above; 2) with verb zadan "to make, to do," originally "to strike, beat; to do; to play an instrument" (Mid.Pers. zatan, žatan; O.Pers./Av. jan-, gan- "to strike, hit, smite, kill" (jantar- "smiter"); cf. Skt. han- "to strike, beat" (hantar- "smiter, killer"); Gk. theinein "to strike;" L. fendere "to strike, push;" Gmc. *gundjo "war, battle;" PIE *gwhen- "to strike, kill").
Fr.: masque, masquage
1) A method of improving → spatial resolution
of images. → pupil masking;
→ unsharp masking.
Verbal noun of → mask.
1) jerm (#), qond (#); 2) tudé (#), anbuh (#)
1) A measure of the amount of material in an object, defined either by the
inertial properties of the object or by its gravitational influence on other
bodies. See also → inertial mass,
→ gravitational mass.
From O.Fr. masse "lump," from L. massa "kneaded dough, lump," from Gk. maza "barley cake, lump, mass, ball," related to massein "to knead."
Jerm, from Ar. jirm.
mass absorption coefficient
hamgar-e daršm-e jermi
Fr.: coefficient d'absorption de masse
A measure of the rate of absorption of radiation, expressed as the linear absorption coefficient divided by the density of the medium through which radiation is passing.
Fr.: défaut de masse
The difference between the rest mass of an atomic nucleus (made up of protons and neutrons) and the sum of the masses of its individual protons and neutrons. The mass difference is equal to the released binding energy. Also called mass deficiency
Fr.: densité massique
The mass per unit area of the ring material, integrated through the thickness of the ring. Sometimes called → surface density (Ellis et al., 2007, Planetary Ring Systems, Springer).
Fr.: écart de masse
1) For → massive stars and → supergiants,
the difference between the → spectroscopic mass and the
→ evolutionary mass. Early studies found that the spectroscopic
mass was systematically less than the evolutionary mass by as much as a factor of 2 for
supergiants. Improvements in the stellar atmosphere models (taking into account
→ line blanketing) have decreased or eliminated the size of the
discrepancy for Galactic stars. There is still a mass discrepancy for the hottest
→ O stars in the → Magellanic Clouds
(See, e.g. Massey et al. 2009, ApJ 692, 618).
Fr.: énergie de masse
The energy (E) associated with a mass (m), as specified by the → mass-energy equivalence E = mc2, where c is the → speed of light. For a moving body the total energy of the particle is expressed by: E2 = m2c4 + p2c2, where m is → rest mass and p → momentum.
Fr.: extinction en masse
An event in the history of life on Earth in which large numbers of species (sometimes more than 90% of some species) vanish in a relatively short period of time. In spite of controversy, it is generally recognized that there have been at least six major mass extinctions. These occurred in the late Cambrian (500 million years ago), in the late Ordovician (440 million years ago), in the late Devonian (365 million years ago), at the end of the Permian (245 million years ago), in the late Triassic (208 million years ago), and at the end of the Cretaceous (65 million years ago).