| Abbreviation | Definition |
|---|---|
| NAOC | National Astronomical Observatory of China |
| NAOJ | National Astronomical Observatory of Japan |
| NAP | Non Astronomical Programme |
| NASA | National Aeronautics and Space Administration |
| NASA | National Airplane Space Airplane |
| NASA | Nerds And Scrubs Association |
| NBS | Next Bright Star |
| NC | Numerical Cosmology |
| NCAS | Northern Colorado Astronomical Society |
| NCP | North Celestial Pole |
| NEAF | North East Astronomy Form |
| NEAF | North East Astronomy Forum |
| NEO | Near Earth Object |
| NEP | North Ecliptic Pole |
| NFAR | Near Field Apertureless Raman |
| NFF | New Firm Formation |
| NGC | New General Catalog |
| NGC | New General Catalogue |
| NGS | National Geographic Society |
| NGS | New Generation Star |