Lunar distance
In celestial navigation, lunar distance is in the angle of the Moon's centre from the Sun or from the bright stars. It is measured using a sextant. Using the lunar distance and a nautical almanac it is possible to calculate the current time and thus the current longitude.
In astronomy, a lunar distance is the distance from the Earth to the moon. The average distance from the Earth to the moon is 384,403 kilometers (238,857 miles).