Glossary
Definitions
8 definitions
CNES (Centre National d'Études Spatiales)
The French national space agency, established in 1961 with an annual budget of approximately €2.8 billion — responsible for France's civil space programme, operating launch facilities at Kourou (Guiana Space Centre), and funding satellite R&D through government programmes and ESA contributions.
COSPAS-SARSAT
An international satellite-based search and rescue system established in 1982 by the USA, Russia, Canada, and France, which detects distress signals from EPIRBs (maritime), ELTs (aviation), and PLBs (personal) at 406 MHz and relays them to ground stations to alert rescue authorities worldwide.
Capacity Lease
The traditional satellite business model where operators sell defined frequency bandwidth and power allocations (transponders, MHz, or Mbps) to service providers under multi-year contracts — typically $1–3 million per transponder per year for GEO Ku-band, with the customer providing their own ground equipment and operations.
Chemical Propulsion
Spacecraft propulsion using the combustion of liquid or solid chemical propellants to generate high thrust — used for orbit insertion, large trajectory corrections, and emergency manoeuvres where rapid delta-v is needed, at the cost of lower specific impulse than electric propulsion.
Collision Avoidance Manoeuvre
A propulsive burn executed by an active satellite to change its trajectory when conjunction analysis predicts a collision probability exceeding regulatory thresholds — typically 1-in-10,000 — consuming propellant and requiring coordination between operators to avoid creating new collision risks.
Conjunction Analysis
The process of comparing predicted orbital trajectories for all tracked space objects to identify close approaches (conjunctions) where collision probability exceeds a defined threshold, typically 1 in 10,000, triggering collision avoidance manoeuvre planning for active spacecraft.
Copernicus Programme
The EU and ESA's Earth observation programme — the world's largest — operating the Sentinel satellite family to deliver free, open, near-real-time data on land, ocean, atmosphere, and emergency management, with over 350 TB of data distributed daily to public and commercial users.
CubeSat
A standardised small satellite format based on 10×10×10 cm modules (1U = max 2 kg), developed in 1999 by Cal Poly and Stanford, that has democratised access to space by enabling universities and startups to build satellites for under $1 million.