NavList:

Sorry. Typo error.
Correction:-

The Moon moves against the background of stars by 30 minutes of arc in one hour.

i.e. one minute of arc in two minutes of time.

i.e. one second of arc in two seconds of time.

Hence a sextant measurement of one second of arc is needed to obtain two seconds in time accuracy, (ignoring any other errors in the method).

As normally only a half a minute of arc is probably the best that can normally be expected or regularly achieved with a sextant (and that only if it is perfectly free from errors in the divisions of the scale and the index error is known to that accuracy) then that implies a theoretical accuracy in time for Lunar Distances of one minute in time achieved.

Douglas Denny.
Chichester. England.
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