Latitude and longitude
Grid fixes any point on Earth with two numbers, one per line family.
| Latitude (parallels) | Longitude (meridians) | |
|---|---|---|
| Lines | Circles parallel to equator | Pole to pole, at right angles to equator |
| Run | East-west | North-south |
| Measure | Degrees north or south of equator | Degrees east or west of Prime Meridian |
| Zero line | Equator | Prime Meridian (through Greenwich, England) |
| Range | 0° to 90°N or 90°S (poles) | 0° to 180°E or 180°W |
- Equator: imaginary circle equidistant from the poles.
- Equator to pole is one-fourth of a circle, so latitude max is 90°.
- Position order: latitude, then longitude.
Examples (TP 13014 sample exam):
| Place | Latitude | Longitude |
|---|---|---|
| Kingston | 44°13'N | 76°35'W |
| Peterborough | 44°13'N | 78°21'W |
Trap: swapping families: latitude (parallels) runs east-west, measures north/south, max 90°; longitude (meridians) runs north-south, measures east/west, max 180°.
References
- PHAK ch.16 (FAA-H-8083-25) Latitude and Longitude (Meridians and Parallels)
- TP 13014 sample exam (Kingston and Peterborough coordinates)