NASA Abbreviations and Acronyms

1. HEM-V
   Helium Manual Valve
2. HEMI
   Hemispherical (s-band Antenna)
3. HEMIL
   hardware evaluator, man in loop
4. HEMV
   Helium Manual Valve
5. HEO
   High Earth Orbit
6. HEO
   Highly Elliptical Orbit
7. HEO
   High Energy Orbit
8. HEOO
   Honeywell Electro-Optical Operations
9. HEOR
   Historical Event Operation Record
10. HEOS
    High Endo Designator Sensor
11. HEPA
    High Efficiency Particulate Air
12. HEPAD
    High Energy Pjoton and Alpha Particle
13. HER
    Him Equipment Rack
14. HERSCP
    Hazardous Exposure Reduction and Safety Criteria Plan
15. HERT
    Headquarters Emergency Relocation Team
16. HESS
    High-Energy Squib Simulator
17. HESSI
    High Energy Solar Spectroscopic Imager
18. HESSI
    High Energy Squib Simulator Instrument
19. HETM
    Hybrid Engineering Test Model
20. HEX
    Heat Exchanger

Last updated: May 6, 2025 — Total entries: 14,020