EUROPE · GLOSSARY
Terms explained simply
A few technical terms cannot be avoided in space travel. They are explained here in simple words.
- Launch Window
- The period during which a rocket can launch so that the satellite reaches its target orbit. Sometimes only seconds, sometimes hours.
- “No earlier than” and “Planned for”
- “No earlier than 23 Nov” means the source names a day, but the launch may still move. “Planned for 2027” is only a rough plan. We never show dates more precisely than the source provides.
- Orbit (orbit)
- The path of a satellite around the Earth. It constantly falls towards the Earth, but is so fast that it always misses it.
- Low Earth orbit
- Orbits up to about 2,000 km altitude. The ISS flies around 400 km high and orbits the Earth in about one and a half hours.
- About the poles (sun-synchronous)
- Earth observation and weather satellites often fly over the poles. They cross every location at the same local time, making it easy to compare images.
- Medium height
- Approximately 20,000 to 23,000 km. Navigation satellites like Galileo orbit there.
- Geostationary
- Approximately 36,000 km above the equator. A satellite there appears to stand still over a point on Earth – ideal for weather images and television.
- Carrier rocket
- The rocket that brings a satellite into space, such as Ariane 6 or Vega-C.
- Payload
- What the rocket transports: satellites, space probes or cargo.
- Boosters and upper stage
- Boosters provide additional thrust during launches and are separated early. The upper stage brings the payload to its final orbit.
- Orbital elements
- Numbers that describe an orbit. From them, we calculate the positions in the 3D view and the ISS viewing windows.
- Flyby
- A space probe uses the gravity of a planet to change speed and direction – this is how Juice saves fuel on its way to Jupiter.
Automatically translated from German; some interface labels are reviewed. View original →. Some new text is still available in German.