Line of Position

A Line Of Position or position line is derived from celestial observations.[1]

The combination of the angle of observation of a celestial body (sun, moon, planet, star) with an exact time of day allows the observer to calculate one line of position on the face of the earth that corresponds to that observation.

Observations of two celestial bodies and two lines of position allow a navigator to "fix" a position, in theory. Limits of the instruments, movement between two observations, the precision of the chronometer, and the skill of the observer affect the precision of a calculated position.

• "We are on the line 157 337."
• How Earhart and Noonan could have derived 157/377 at dawn.
• Celestial navigation.