An equatorial advantage
The Guiana Space Centre, or Centre Spatial Guyanais (CSG), is Europe's primary spaceport for a simple reason: physics. Located at a latitude of 5° North, its proximity to the equator gives a velocity boost to rockets at launch. The Earth rotates fastest at its equator, reaching a speed of about 460 meters per second (1,670 km/h). By launching eastward, rockets get this rotational speed for free, an effect often called a "slingshot." This extra momentum means rockets use less propellant to reach orbit, allowing them to carry heavier payloads. For example, an Ariane 5 rocket launching from Kourou can deliver over 10,000 kg to Geostationary Transfer Orbit (GTO), whereas a similar rocket from a high-latitude site might be limited to around 6,300 kg. A Soyuz rocket's payload capacity to GTO increases by more than 60% compared to launching from the Baikonur Cosmodrome in Kazakhstan.
The site, selected in 1964 after France had to leave its previous base in newly independent Algeria, has other important geographic benefits. It has open ocean to the east and north, providing a safe corridor for spent rocket stages to fall without endangering populations. The region also has a low population density and is not prone to major seismic activity or the tropical cyclones and hurricanes that can affect other launch sites like Cape Canaveral.
Europe's launch workhorses
The CSG is a spaceport designed to accommodate a fleet of different vehicles managed by Arianespace. The workhorse for decades has been the Ariane family of rockets, culminating in the Ariane 5, a heavy-lift launcher capable of placing more than 20 metric tons into Low Earth Orbit. Its successor, Ariane 6, is designed to continue Europe's capability for heavy launches. The launch complex for Ariane 5, ELA-3 (Ensemble de Lancement Ariane 3), includes a massive 90-meter-tall Final Assembly Building where the rocket is assembled vertically on a mobile launch table before being transported 2.8 km to the launch pad.
From 2011 until early 2022, the CSG also hosted the Russian Soyuz rocket, a medium-lift vehicle with a long history of reliability. This partnership gave Arianespace more flexibility, bridging the gap between heavy and light launchers. The Soyuz launch complex (ELS) was built 12 km northwest of the Ariane pads and was adapted for the tropical climate. For smaller payloads, Europe relies on the Vega rocket, a light-lift launcher designed to carry about 1,500 kg into a 700-km altitude orbit. This trio of launchers allowed the CSG to cover the full range of satellite sizes.
The entire 700-square-kilometer facility is a high-security zone. Protection is provided by French Gendarmerie and the 3rd Foreign Infantry Regiment of the French Foreign Legion, who patrol the vast perimeter.
A history of landmark missions
The first launch from CSG was a Véronique sounding rocket on April 9, 1968, and the first orbital launch occurred on March 10, 1970. a milestone was the first Ariane 1 launch on Christmas Eve, 1979, which established Europe's independent access to space.
Since then, Kourou has been the starting point for modern science's important missions. The James Webb Space Telescope, the largest space observatory ever built, was launched from CSG aboard an Ariane 5 on December 25, 2021. The Rosetta mission, which successfully orbited and landed a probe on comet 67P/Churyumov–Gerasimenko, began its decade-long journey from French Guiana in 2004. Other notable launches include the JUICE (JUpiter ICy moons Explorer) probe in 2023, destined for the Jovian system, and numerous satellites for Europe's Galileo global navigation system.