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Lu, in an earlier message, you wrote parenthetically:
"although Richard Feynman claimed that a positron
(positively charged electron) was in fact an electron moving backwards
in time."

This is miles from navigation, but I can't resist... Feynman's idea is
considered uncontroversial today. A positron IS an electron going backward
in time. But in the restricted sense that it carries no causality
information. It's not a "time traveler" going back to kill its positronic
grandfather and throw the universe into chaos. It's merely mathematically
identical to an electron going backward in time. The future, with respect to
causality, is the direction in which entropy increases, and fundamental
particles don't know anything about that.

And you wrote:
"And that last sentence is the key to your question of "how would I
practice celestial navigation if we didn't have leap seconds"   As long
as I could convert my local time into Almanac time, it wouldn't matter,
just as I adjust from local time to GMT."

So you also agree that it would be no issue, right? The author of the time
article suggested that the "vanishing breed" of celestial navigators would
be upset over the abolition of leap seconds. I think that's incorrect. We
would have little problem adjusting the rules in a world without
leapseconds. But I'm still interested in some of the options as to how this
might be done. Suppose I publish a nautical almanac today for the year 2058.
How could I use it correctly for celestial navigation in that year? Adjust
the input time?? Adjust the longitude at the end?? If I wait until 2057 to
publish that almanac, it seems that the best approach would be the one Paul
suggested: fold the longitude difference into the published GHA values.

 -FER

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