| Abbreviation | Definition |
|---|---|
| FCAD | Five College Astronomy Department |
| FFD | First Fixation Duration |
| FFTW | Fastest Fourier Transform in the West |
| FGC | Flat Galaxy Catalogue |
| FIGV | Factor Inercial de Ganho solar do enVidracado |
| FIMS | FORS Instrumental Mask Simulator |
| FIRST | Frontiers In Research Space and Time |
| FOC | Faint Object Camera |
| FOCAS | Faint Object Classification and Analysis System |
| FOP | Friends Of Phobos |
| FP | Frozen Planet |
| FR | Fanaroff-Riley |
| FRAS | Fellow of the Royal Astronomical Society |
| FRB(s) | gamma ray burst(s) |
| FRONT | Front Range Observational Network Testbed |
| FS | Far Side |
| FU | Forces Unknown |
| G | Gravity |
| GAAC | Gloucester Area Astronomy Club |
| GAF | Geographic Adjustment Factor |