| Aestus | Engine of the Ariane-5 upper storable propellant stage |
| Apogee | Furthest point from Earth of an orbit |
| Ariane launch zone | Area at Europe’s Spaceport from where the Ariane 5 lifts off |
| Attitude | The orientation of a spacecraft in relation to its direction of motion |
| BAF | see Final Assembly Building |
| BEAP | see Booster Engine Test Stand |
| BIL | see Launcher Integration Building |
| BIP | see Booster Integration Building |
| Booster | Boosters are added to a launcher to provide the main thrust at liftoff - they consist of a casing containing the propellant, a solid rocket motor and additional equipment such as the igniter and the forward skirt equipped with a recovery system
Etage d'accéleration à poudre (EAP) |
| Booster Casing Preparation Building | Building at the Spaceport where the booster casings are prepared
Batiment préparation étage (BPE) |
| Booster Engine Test Stand | Place where booster engines are tested at Europe's Spaceport
Banc d'essais des accélération à poudre (BEAP) |
| Booster Integration Building | Building at the Spaceport where the integration of the Ariane-5 solid booster stage takes place
Bâtiment d'intégration des propulseurs (BIP) |
| Booster Separation Rockets | These separate the booster from the launch vehicle after approximately two minutes flight |
| Booster Storage Building | Place at Europe's Spaceport where the boosters are stored until needed
Bâtiment Stockage Etage (BSE) |
| BSE | Bâtiment stockage Etage see Booster Storage Building |
| CNES | Centre National d'Etudes Spatiales, French Space Agency |
| Constellation | Space network composed of multiple small satellites, generally placed in low Earth or intermediary orbits |
| Cryogenic propulsion | High performance propulsion that uses liquid hydrogen propellant and liquid oxygen as oxydiser |
| CSG | Centre Spatial Guyanais - Guiana Space Centre also known as Europe's Spaceport |
| DAAR | Dispositif d'Accrochage Arrière - Rear booster attachment and release mechanism |
| DAAV | Dispositif d'Accrochage Avant - Forward booster attachment and release mechanism |
| EAP | Etage Accélérateur à Poudre - see booster |
| ELA-3 | Ariane-5 launch complex containing the Launcher Integration Building, the Final Assembly Building, the Solid Propellant Booster Integration Building and the propellant plants |
| EPC | Etage Principal Cryogénique - see Main cryogenic stage |
| EPCU S5 | Ensemble de Préparation des Charges Utiles - see Satellite Preparation Facility |
| EPS | see Storable propellant stage |
| ESA | European Space Agency |
| Fairing | Used to protect satellites before and during the launch, and while crossing the lower levels of the atmosphere; it is jettisoned once the launcher leaves the Earth's orbit |
| Final Assembly Building | Place at Europe's Spaceport where the launcher is finally assembled with the payload and checks are carried out
Bâtiment d'Assemblage Final (BAF) |
| GEO | see Geostationary orbit |
| Geostationary orbit | An orbit which circles the Earth above the equator from east to west at an attitude of 36 000 km (GEO) |
| Geostationary transfer orbit | An elliptical orbit whose apogee is at approximately 36 000 km, used to place a satellite into GEO (GTO) |
| GTO | see Geostationary transfer orbit |
| Guiana Space Centre | The French Space Centre in French Guiana also known as Europe's Spaceport
Centre Spatial Guyanais (CSG) |
| Hydrazine | A colourless basic liquid made from sodium hypochlorite and ammonia used chiefly as a rocket fuel |
| Interstage | This provides the mechanical interface between two launcher stages and also hosts the separation device, the thrust vector control electrical unit and the batteries |
| Jupiter Control Centre | Ariane-5 mission control building |
| Launch zone | The launcher is transferred to this area 48 hours before launch for final propellant filling, countdown and launch |
| Launcher Integration Building | Place at Europe's Spaceport where the launcher's main stage is integrated with the boosters
Bâtiment d'Intégration Lanceur (BIL) |
| LEO | see Low Earth orbit |
| LH2 Plant | Facilities at Europe's Spaceport for producing liquid hydrogen for the Ariane-5 main cryogenic stage engine |
| Low Earth orbit | Generally considered to be an orbit at an altitude of 400 to 1000 km (LEO) |
| LOX Plant | Facilities at Europe's Spaceport for producing liquid oxygen for the Ariane-5 main stage and the Vulcain engine |
| Main cryogenic stage | The main cryogenic stage of the Ariane 5 includes the cryogenic tank and the Vulcain engine; the duration of burnout is about 10 mins - the time needed for the launcher to leave the Earth's atmosphere
Etage Principal Cryotechnique (EPC) |
| MPS | Moteur Propergol Solide - the booster's solid rocket motor |
| Orbit | The path followed by a satellite around a celestial body |
| P80 solid rocket motor | Vega's first stage motor with a combustion time of 107 s |
| Payload | The useful mass that can be carried and injected into orbit by a launcher; it could be a satellite, a module or a capsule |
| Payload adapters | A device used to support satellites |
| Perigee | Point of an orbit closest to the Earth |
| Polar orbit | An orbit that passes over the polar regions from north to south |
| Satellite Preparation Facility | Complex at Europe's Spaceport where satellites are prepared for launch
Ensemble de preparation de charges utiles (EPCU S5) |
| Skirt | Structure that joins together two parts of a launcher's or booster's stage and which transmits mechanical forces from the engine to the other structures of the launcher |
| Solid Booster Integration Building | Place at Europe's Spaceport where booster segments are integrated
Bâtiment d'intégration des propulseurs (BIP) |
| Solid rocket motor | Motor of the Ariane-5 solid propellant booster (MPS) |
| Soyuz launch zone | Area at Europe's Spaceport from where the Russian Federeation Soyuz launcher will lift off in 2007 |
| Speltra | Multiple launch carrier structure that supports the upper payload and encapsulates the lower payload, protecting it from acoustic vibrations and thermal flow |
| Stage | Term used for a complete element of a launch vehicle, i.e. propellant tank, one or more engines and electrical, mechanical or pneumatic equipment |
| Storable propellant stage | This is the Ariane-5 upper stage - after 25 mins of thrust this reaches the orbiting speed of 28 000 km/h needed to release satellites into GTO
Etage à propergols stockables (EPS) |
| SSO | see Sun-synchronous orbit |
| Sun-synchronous orbit | A polar orbit which is synchronous with the Sun, usually at an altitude of between 600-800 km (SSO) |
| Sylda-5 | Multiple launch carrier structure housed inside the fairing - the Sylda 5 is smaller than the Speltra |
| Technical Centre | Administration buildings and control rooms at the Spaceport |
| Telemetry | Telecommunication of the readings of measuring instruments to a device on which the readings can be indicated or recorded |
| UPG | Solid-propellant plant at Europe's Spaceport
Usine de propergol de Guyane (UPG) |
| VEB | see Vehicle equipment bay |
| Vega | A European launcher schedule to make its first flight in 2006 from Europe's Spaceport |
| Vega launch zone | Area at Europe's Spaceport from where Vega will lift off |
| Vega AVUM upper stage | Upper stage of Vega consisting of a liquid propellant system, an attitude control system and the core of Vega's avionics system |
| Vehicle equipment bay | The brains of an Ariane-5 launcher, this groups the main electronic elements that control the launcher |
| Vulcain engine | Cryogenic engine of the Ariane-5G main stage |
| Zefiro 23 solid rocket motor | The Vega second stage motor with a combustion time of 71.6 s |
| Zefiro 9 solid rocket motor | Vega 3rd stage solid rocket motor with a combustion time of 110 s |
| ZL | Zone de lancement see Launch zone |
| ZLA | see Ariane 5 launch zone |
| ZLS | see Soyuz launch zone |
| ZLV | see Vega launch zone |
