A measurement of the position of the moon in order to calculate longitude from lunar distance.
月球观测
Example sentencesExamples
He speculated that he would continue to ‘amuse’ himself in attempting to determine Monticello's longitude but with lunar observations.
At the Greenwich Royal Observatory Halley used the first transit instrument and devised a method for determining longitude at sea by means of lunar observations.
If you had a chronometer, you would use it to measure longitude all the time, not just "when lunar observations were impractical."
Definition of lunar observation in US English:
lunar observation
noun
A measurement of the position of the moon in order to calculate longitude from lunar distance.
月球观测
Example sentencesExamples
At the Greenwich Royal Observatory Halley used the first transit instrument and devised a method for determining longitude at sea by means of lunar observations.
He speculated that he would continue to ‘amuse’ himself in attempting to determine Monticello's longitude but with lunar observations.
If you had a chronometer, you would use it to measure longitude all the time, not just "when lunar observations were impractical."