Quote:
Originally Posted by The Mekon
A few questions remain - The yearbook only tabulates to the nearest minute – mariners are used to working to the nearest second, so the accuracy could be less than that stated above.
Also I am assuming that the timing in the yearbook is for the end of the event (i.e. the completed occultation) and not the beginning (first contact)
Any comments are most welcome. John
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Hi John,
I assume your observation was on the 26th June.
Occult (by Dave Herald) lists this event as occurring at 9:18.7 UT (= 19:18:42 AEST) See attached file. I've marked the event with a <
I'm not sure how the yearbook times the event but Occult gives times for mid-event.
It's my understanding that navigators used the lunar distance method to determine longitude at sea before Harrison and his clocks solved the puzzle. Navigators could use a sextant to measure the various angles from the deck of a moving ship. Usually, the Master, the Captain and several lieutenants made the observations and an average was taken. Cook was highly proficient at reducing the observations to a longitude value, even then the task took several hours of hard work.
Now we have GPS. Thanks US taxpayers.
