Space Industry Glossary: 69 Essential Terms Every Professional Should Know
From apogee to zero-gravity, from ITAR to TRL — the definitive glossary of space industry terms for professionals, investors, and enthusiasts.
The space industry has its own language. Whether you're joining from finance, tech, or policy, mastering the terminology is essential for credibility and efficiency. Here are the 69 terms you'll encounter most often.
Orbital Mechanics
- LEO (Low Earth Orbit): 200-2,000 km altitude. Home to ISS, Starlink, and most Earth observation satellites. Orbital period: ~90 minutes
- MEO (Medium Earth Orbit): 2,000-35,786 km. GPS and navigation constellations operate here
- GEO (Geostationary Earth Orbit): 35,786 km. Satellites appear stationary over one point. Used for communications and weather
- TLE (Two-Line Element): Standardized format for describing a satellite's orbit. Used by the SGP4 propagation model
- Delta-V: Change in velocity needed for an orbital maneuver. The fundamental currency of spaceflight
- Apogee/Perigee: Highest/lowest point in an elliptical orbit around Earth
Business & Investment
- NewSpace: The commercial space industry wave driven by private investment and entrepreneurial companies (vs. traditional government/prime contractors)
- Space Economy: All economic activity related to space — currently ~$630B and growing at 9% annually
- SBIR: Small Business Innovation Research — non-dilutive government grants for technology development
- TRL (Technology Readiness Level): NASA's 1-9 scale for technology maturity. TRL 1 = basic research. TRL 9 = flight-proven
- Flight Heritage: Proven track record of a technology or component operating successfully in space
Regulatory & Compliance
- ITAR: International Traffic in Arms Regulations — US export controls on defense-related space technology
- EAR: Export Administration Regulations — US controls on dual-use commercial space technology
- FCC: Federal Communications Commission — licenses satellite spectrum and orbital slots for US operators
- ITU: International Telecommunication Union — coordinates global spectrum allocation
Explore the full interactive glossary with 69 terms across 12 categories at SpaceNexus Glossary. Or browse our Space Acronyms directory with 126+ entries.
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