An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



<< < age Moo > >>

Number of Results: 40 Search : Moon
Moon's prime meridian
  نیمروزان ِ نخستی ِ مانگ   
nimruzân-e naxosti-ye Mâng

Fr.: méridien origine de la lune   

The line connecting the Moon's north pole with its south pole, and passing through the center of the lunar disk. The longitude of the Moon's prime meridian is zero degrees.

Moon; → prime meridian.


Fr.: arc en ciel lunaire   

A rainbow that arises from the refraction and reflection of moonlight on rain drops or mist.

moon; → bow.


Fr.: satellite mineur, lune mineure   

A very small natural or artificial satellite orbiting a planet. Saturn has dozens of moonlets often associated with its → planetary rings.

moon; → -let.

moonlet wake
  کل ِ مانگچه   
kel-e mângcé

Fr.: sillage de lune mineure   

Local disturbances in the ring structure caused by the gravitational influence of embedded satellites. If the satellite (moonlet) is large enough to clear a gap in the rings, the moonlet wakes become edge waves that precede the satellite on the inner edge and trail the satellite on the outer edge. For smaller satellites, the "gap-less" wakes have been nicknamed propellors (Ellis et al., 2007, Planetary Ring Systems, Springer).

moonlet; → wake.

mahtâb (#)

Fr.: clair de lune   

The light of the Moon.

From → moon + → light.

Mahtâb (Gilaki mângtâb) from mah, mâh (mâng), → moon, + tâb "light," from tâbidan, tâftan "to shine," tafsidan "to become hot" (Av. tāp-, taf- "to warm up, heat," tafsat "became hot," tāpaiieiti "to create warmth;" cf. Skt. tap- "to spoil, injure, damage; to suffer; to heat, be/become hot," tapati "burns;" L. tepere "to be warm," tepidus "warm;" PIE base *tep- "warm").


Fr.: tremblement de lune   

A → seismic event occurring on the → Moon; the lunar equivalent of an → earthquake. Moonquakes were first detected by the → seismometers placed on the Moon by Apollo astronauts from 1969 through 1972. The instruments placed by the Apollo 12, 14, 15, and 16 missions were functional until 1977. Unlike earthquakes, moonquakes are not believed to be caused by → tectonic plate movement, but by → tidal forces between Earth and the Moon. There are at least four different kinds of moonquakes: (1) deep moonquakes about 700 km below the surface. They occur at monthly intervals at about 100 distinct sites, indicating that these moonquakes are caused by → stresses from changes in lunar tides as the Moon orbits the Earth; (2) vibrations from the impact of → meteorites; (3) thermal quakes caused by the expansion of the frigid crust when first illuminated by the morning sun after two weeks of deep-freeze lunar night; and (4) shallow moonquakes only 20 or 30 km below the surface (

moon; → quake.

  بر‌آمد ِ ماه   
barâmad-e mâh (#)

Fr.: lever de la lune   

The times at which the apparent upper limb of the ascending Moon is on the astronomical horizon.

moon; → rise.

  فروشد ِ مانگ   
forušod-e mâng (#)

Fr.: coucher de la lune   

The crossing of the visible horizon by the upper limb of the descending Moon.

moon; → set.

moonset lag
  لک ِ فروشد ِ مانگ   
lek-e forušod-e mâng

Fr.: retard du coucher de la lune   

The delay between → sunset and → moonset.

moonset; → lag.

new moon
  نومانگ، مانگ ِ نو   
nowmâng (#), mâng-e now (#)

Fr.: nouvelle lune   

The Moon's phase when it is at the same celestial longitude as the Sun and thus totally un-illuminated as seen from Earth.

new; → moon.

perigee full Moon
  پرمانگ ِ پیرازم   
pormâng-e pirâzam

Fr.: pleine lune de périgée   

The → full Moon when our natural satellite is at its closest approach to the Earth. Perigee full Moons are as much as 14% larger and 30% brighter than → apogee full Moons. Also called perigee-syzygy full Moon, super full Moon, and → supermoon. The Supermoon on November 14, 2016, was the closest (356,523 km) a Full Moon has been to Earth since January 26, 1948. The next time a Full Moon is even closer to Earth (356,448 km) will be on November 25, 2034.

perigee; → full; → moon.

perigee-syzygy full Moon
  پرمانگ ِ پیراهور-یوجان   
pormâng-e pirâhur-yujân

Fr.: lune de périgéé-syzygie   

perigee full Moon.

perigee-; → syzygy; → full; → moon.

phases of the Moon
  سیماهای ِ مانگ   
simâhâ-ye Mâng

Fr.: phases de la lune   

Lunar phase.

phase; → Moon.

shepherd moon
  مانگ ِ چوپان   
mâng-e cupân

Fr.: satellites bergers   

A → natural satellite in orbit near the edge of a → planetary ring, whose → gravitational force on the ring particles strongly controls the distribution of material within the ring, creating ringlets and density waves within the ring and sharp edges at ring boundaries. Examples include → Saturn's → Prometheus and → Pandora, which shepherd the narrow outer → F ring and the → Uranus satellites → Cordelia and → Ophelia and the epsilon ring. The faster-moving inside satellite accelerates the inner ring particles as it passes them, causing them to spiral out to larger orbits. At the same time the slower-moving outer satellite decelerates the outer ring particles as they pass by, causing them to spiral inward. The result is a narrow, well-defined ring.

shepherd; → moon.

Sodium Moon Spot (SMS)
  لکه‌ی ِ سودیومی ِ مانگ   
lake-ye sodiomi-ye Mâng

Fr.: tache de sodium de la Lune   

The → sodium tail of the Moon as it appears in the sky opposite the Sun. The SMS undergoes changes in shape and brightness. It is brighter when the → new moon occurs at → perigee, when the new moon is north of the → ecliptic, and approximately five hours after the new moon.

sodium; → Moon; → spot.

sodium tail of the Moon
  دنباله‌ی ِ سودیومی ِ مانگ   
donbâle-ye sodiomi-ye Mâng

Fr.: queue de sodium de la Lune   

A comet-like tail of the Moon comprised of → sodium (Na) atoms and invisible to the naked eye. The lunar surface is constantly bombarded by the → solar wind, → photons, and → meteoroids, which can liberate Na atoms from the → regolith. These atoms are subsequently accelerated by solar → radiation pressure to form a long comet-like tail opposite the Sun. Near → new moon, this diffuse cloud of Na atoms encounters the Earth's gravity and is "pinched" into a beam of enhanced density. This beam appears as the ~3° diameter Sodium Moon Spot (SMS) seen in the sky opposite the Sun. The spot is about five times the diameter of the → full moon, and is 50 times fainter than can be seen with the unaided eye. The spot is reflected light from millions of Na atoms that two days earlier were on the surface of the Moon. This spot is visible to sensitive cameras equipped with filters tuned to the orange light emitted by Na atoms near 589.3 nm (Baumgardner et al., 2021 Journal of Geophysical Research: Planets DOI: 10.1029/2020je006671).

sodium; → tail; → Moon.

super Moon
  ابر ماه   
abar mâh

Fr.: pleine lune de périgée   

Same as → perigee full Moon.

super-; → Moon.


Fr.: super lune   

Same as → perigee full Moon.

super-; → moon.

waning moon
  مانگ ِ کاهنده   
m mâng-e kâhandé (#)

Fr.: lune descendante   

The circumstance when the phase of the Moon is decreasing from → full moon to → new moon.

waning; → moon.

waxing moon
  مانگ ِ فزاینده   
mâng-e fazâyandé (#)

Fr.: lune montante   

The circumstance when the phase of the Moon is increasing from → new moon to → full moon.

waxing; → moon.

<< < age Moo > >>