ball tup (#), guy (#) Fr.: boule, balle, ballon A spherical or approximately spherical body, either solid or hollow. From M.E. bal, balle, from O.Fr.; cf. O.H.G. ballo, Ger. Ball; PIE root *bhel- "to blow, swell." Tup "ball," initially "clmup, aggregation, parcel, group" (tup tup "many"); Tabari tupa "compressed, assembled," tuppi "round;" Kurd. top "ball," topâl "round;" guy, → globe. |
ball lightning gu-ye âzaraxš (#) Fr.: foudre en bulle A rare form of lightning occurring as a bright red globe observed floating or moving through the atmosphere close to the ground. It usually is seen shortly before or after, or during, a → thunderstorm. Its duration varies from a few seconds to a few minutes. See also → Saint Elmo's fire. |
ballistic partâbik (#) Fr.: balistique Of or relating to → ballistics. |
ballistic missile mušak-e partâbik (#) Fr.: missile balistique A missile that after being launched and guided in the early part of its flight, travels unpowered in a ballistic trajectory. |
ballistic panspermia pân-dâne-vari-ye partâbik Fr.: panspermie balistique Transfer of microbes and biochemical compounds from a planet to another due to meteoric impacts. Debris being knocked off a planet like Mars can reach escape velocity and enter the atmosphere of another planet with passenger micro-organisms intact. → ballistic; → panspermia. |
ballistic trajectory tarâyeš-e partâbik Fr.: trajectoire balistique A curved path followed by an unpowered object that is being acted upon only by gravitational forces and the friction of the medium through which it moves. → ballistic; → trajectory. |
ballistic wave mowj-e partâbik Fr.: onde balistique Audible disturbance or wave caused by the compression of air ahead of a projectile in flight. |
ballistics partâbik (#), partâbšenâsi (#) Fr.: balistique The science of the motion and behavior of → projectiles. The study of the functioning of firearms. From L. ballista "ancient military machine for hurling stones," from Gk. ballistes, from ballein "to throw," from PIE *gwelH1- "to throw;" cf. Pers. garzin "arrow;" Av. niγr- "to throw down;" Khotanese (+ *abi-, *ui-) bīr- "to throw, sow;" Proto-Iranian *garH- "to throw." Partâbik, from partâb "a throw, an arrow that flies far," partâbidan "to throw," + -ik, → -ics; partâbšenâsi, from partâb + -šenâsi, → -logy. |
balloon astronomy axtaršenâsi bâ bâlon, bâlon-axtaršenâsi Fr.: astronomie en ballon A branch of modern astronomy in which balloons are used to carry telescopes and instruments to high altitudes (up to 50 km) for observation. Balloon, from Fr. ballon, from It. dialectal ballone, augmentative of balla, ball, from P.Gmc. *ball-, from PIE *bhel- "to blow, swell". → astronomy. Axtaršenâsi, → astronomy; bâlon, from Fr. ballon. |
balloon-borne telescope durbin-e bâlon-bord, teleskop-e ~ Fr.: télescope porté par ballon A remotely guided or automatic telescope carried to high altitudes by a balloon. → balloon astronomy; borne "a past participle of bear," from O.E. beran "bear, bring, wear," from P.Gmc. *beranan (O.H.G. beran, Goth. bairan "to carry"), from PIE root *bher-; "to carry;" compare with Av./O.Pers. bar- "to bear, carry," bareθre "to bear (infinitive)," bareθri "a female that bears (children), a mother," Mod.Pers. bordan "to carry," Skt. bharati "he carries," Gk. pherein, L. fero "to carry." → telescope. → balloon astronomy. Bord in bâlon-bord "borne, carried," from Mod.Pers. bordan "to bear, carry," as explained above. Durbin, → telescope. |
dirty iceball model model-e golule-ye yax Fr.: modèle de la boule de glace sale A model for a → cometary nucleus proposed by Fred Whipple (1950-51), according to which the nucleus is a solid body (a few kilometers across) made up of various → ices (→ frozen water, → methane, → ammonia, → carbon dioxide, and → hydrogen cyanide) in which → dust is embedded. Dust particles are liberated when the ices vaporize as the → comet approaches the → Sun, and they get blown away by → solar radiation pressure, often forming impressive, gently curved → dust tails. |
fireball tašguy (#), âzarguy (#) Fr.: boule de feu A → meteor that is brighter than the brightest planets, i.e. with an apparent magnitude of -5 or greater. Fireballs are often followed by → meteorite falls. Also called → bolide. From → fire + ball, from O.E., from O.N. bollr "ball," from P.Gmc. *balluz (cf. O.H.G. ballo, Ger. Ball), from PIE base *bhel- "to swell." Tašguy, from taš "fire," variant of âtaš→ fire + guy "ball, sphere," variants golulé, gullé, goruk, gulu, gudé (cf. Skt. guda- "ball, mouthful, lump, tumour," Pali gula- "ball," Gk. gloutos "rump," L. glomus "ball," globus "globe," Ger. Kugel, E. clot; PIE *gel- "to make into a ball"). |
snowball barf-gule Fr.: boule de neige A mass of snow packed into a ball or rolled together, as for throwing. |
snowball Earth Zamin-e barf-gule Fr.: Terre boule de neige Any of several episodes in the history of the Earth where our planet was entirely covered by glacial ice from pole to pole. There are at least three such episodes. The first one, called the Huronian glaciation, extended from 2.4 billion years ago to 2.1 billion years (lasting about 300 million years). In the last billion years, the Earth has experienced two more global glaciations: the Sturtian glaciation, which began 720 million years ago and, following a brief interglacial episode, the Marinoan glaciation, which ended 635 million years ago. During such episodes the global mean temperature would be about -50°C because most of the Sun's radiation would be reflected back to space by the icy surface. The average equatorial temperature would be about -20°C, roughly similar to present Antarctica. Without the moderating effect of the oceans, temperature fluctuations associated with the day-night and seasonal cycles would be greatly enhanced. Because of its solid surface, the climate on a snowball earth would have much in common with present Mars (http://www.snowballearth.org). The term snowball Earth was coined in 1989 by Joe Kirschvink, a biomagnetist and paleomagnetist at the Caifornia Institute of Technology in Pasadena, USA; → earth. |
sounding balloon bâlon-e gamâne-zani Fr.: ballon-sonde A small, free balloon sent into the upper atmosphere to measure, record, and transmit meteorological reports to a ground station. |