Ariane
Ariane
(a-ree-an ) The three-stage launch vehicle built for the European Space Agency (ESA). The building program was officially approved in 1973, financed mainly by France. The original version, Ariane-1, first flew in Dec. 1979; its first successful operational flight took place in June 1983. Responsibility for production and marketing of Ariane was then transferred to the company Arianespace, which had been set up in 1980 to finance, build, sell, and launch Ariane; its first launch occurred in May 1984.The launch site for Ariane is near the equator, at Kourou, French Guiana. The rocket is optimized for launching craft into geostationary orbit (that is, to an altitude of 36 000 km above the equator) for communications and meteorological purpose, into lower Earth orbits for scientific missions, and into Sun-synchronous Earth orbits for terrestrial observations. Ariane is an expendable probe, unlike NASA's reusable space shuttle.
Ariane-1 could carry a payload of up to 1.8 tonnes (1800 kg) into geostationary orbit. As the mass of satellites increased, Ariane-1 gave way, from 1984, to the more powerful Ariane-2 and Ariane-3. These in turn were superseded, from 1988, by the six versions of Ariane-4 – one ‘bare’, the others fitted with two or four solid-fuel booster rockets, depending on the payload mass. The most powerful Ariane-4, with four liquid-fuel boosters, can lift up to 4.46 tonnes into geostationary orbit.
Ariane-5 is radically different from the earlier Arianes. Shorter and squatter, it has two sections. The main unit is the ‘lower composite’, with engine and propellant flanked by two solid boosters, and is the same for all missions; the ‘upper composite’ is matched to the mission and its payload. It is designed to launch one, two, or three satellites weighing up to about 7 tonnes into geostationary orbit, 23 tonnes into low Earth orbit, or 10 tonnes into Sun-synchronous orbit. Its first launch in 1996 ended in disaster with total destruction after a flight of only 40 seconds. But by 2002 it had successfully launched several commercial craft, mostly communications satellites. The catastrophic launch failure of an upgraded version of Ariane-5 in December of that year, with the loss of two communications satellites, proved a major setback for ESA. Following the resumption of its launch program in April 2003, Ariane-5 continued to be used for commercial work and also for important European science missions – the lunar orbiter SMART-1 and the comet interceptor probe Rosetta. In 2007 Ariane-5 will simultaneously carry both the Planck and Herschel Observatories into space.