A small tail-like structure on a comet that, unlike most comet tails, seems to point toward the Sun. This rare event is an optical illusion due to larger dust particles left along the comet's orbit. And typically occurs when the Earth crosses the plane of the comet's orbit. It seen when the observer is in the plane of the cometary orbit.
Pâddom, from pâd-, → anti-, + dom "tail."
Fr.: queue de comète
A formation of → gas and/or → dust that streams away from the → coma of many comets under the influence of the Sun's → radiation pressure and the → solar wind. See also: → dust tail, → gas tail, → ion tail, → plasma tail, → sodium tail, → Type I tail, → Type II tail, → antitail.
1) pâzé; 2) pâzidan
Fr.: 1) détail; 2) détailler
1) An individual or minute part; an item or → particular.
From Fr. détail, from O.Fr. detail "small piece or quantity," literally "a cutting in pieces," from detaillier "to cut in pieces," from → de- "entirely" + taillier "to cut in pieces," from L. taliare "to split."
Pâzé, from Sogd. pâzê "portion, bit;" Kurd. pâž "part of a whole;" related to Mod.Pers. baxš "part, division," bâž "tribute, toll, impost;" ultimately from Proto-Ir. *baj- "to bestow, divide, have a share;" cf. Av. baž- (baxš-) "to divide, bestow, give a share;" O.Pers. bāji- "tribute, tax;" Mid.Pers. bâj, bâž "tribute, tax," baxtan "to distribute," baxt "luck, fate;" Skt. bhaj- "to share, distribute, apportion," Gk. phagein "to eat (to have a share of food)"; PIE base *bhag- "to share out, apportion;" → division.
1) Having many details.
Adjective from → detail.
donbâle-ye qobâri (#)
Fr.: queue de poussière
Fr.: queue de gaz
Fr.: galaxie tête-queue, ~ têtard
A member of the class of radio galaxies (→ radio galaxy) that have a strong radio emission coming from a bright "head" and a more diffuse emission from a "tail." They are often found in clusters.
donbâle-ye yoni (#)
Fr.: queue d'ions
Of a comet, same as → gas tail.
Fr.: queue magnétique
The portion of a planet's → magnetosphere which is pushed away from the Sun by the solar wind. Earth's magnetosphere extends about 65,000 km on the day-side but more than 10 times further.
dom-e natâr, donbâle-ye ~
Fr.: queue neutre
Same as → sodium tail.
Fr.: queue de plasma
The ionized component of a comet's tail, driven nearly straight away from the Sun by the solar wind. Also called ion tail and gas tail.
Fr.: queue de sodium
1) A kind of → cometary tail appearing in some
→ comets, such as → Hale-Bopp.
Sodium tails arise from the very strong → fluorescence
of their sodium atom → D lines
in the visible. They are rapidly accelerated
to high velocities by the Sun, forming a very straight tail distinct from the
→ ion tail.
The release mechanism of sodium from comets is still a matter of debate.
Also called → neutral tail.
dom (#), donbâlé (#)
1) The part that sticks out at the back of an animal's body, and that it can move.
M.E.; O.E. tægl, from P.Gmc. *tagla- (cf. O.H.G. zagal, Ger. Zagel "tail," O.N. tagl "horse's tail").
Dom, variant domb, "tail;" Mid.Pers. dumb "tail;" Av. duma- "tail"; donbâlé, from domb + -âlé, -âl resemblance suffix, → -al.
Fr.: queue de marée
A long stream of stars and gas, often in the form of a spectacular tail, thrown off a galaxy when it collides with another galaxy. → interacting galaxies; → merger. Two tidal tails form in each galaxy, and they are more spectacular when the masses of the two galaxies are comparable, and when their relative orbit is in the same sense as the rotation inside each spiral galaxy.
Type I tail
dom-e gune-ye I
Fr.: queue de type I
The → gas tail of of a comet.
Type II tail
dom-e gune-ye II
Fr.: queue de type II