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Gentlemen (and I hope at least some ladies):

It is hard to keep up with the theoretical and practical comments that
have been exchanged, but it is a welcome challenge. Some follow up
remarks:

1) Bill Noyce's advice on twisting the sextant knob in the same
direction in all situations is well taken. I had not been given that
instruction before but will practice it future.

2) Bruce's "wrong way" tables convert from computed altitude to apparent
altitude to allow the use of calculated altitudes in clearing lunars.
Unless I am missing something, they don't allow one to "unclear" a
calculated lunar distance. If he were willing to share the formulas for
the wrong way tables, it would be possible to create a spreadsheet to
derive periodic apparent altitudes from calculated altitudes, and from
those periodic apparent altitudes, to calculate the apparent lunar
distance, and then sextant distance as it would appear to an observer.
This would allow examination of George's "parallactic retardation" over
an extended period using hourly almanac data. I would be willing to take
a run at this and share the data with the group.

3) George suggested I share the intermediate values I came up with after
I corrected the errors I had made in calculating GMT for my March 22
lunar. Here they are in an abbreviated format that allows me to cut and
paste out of my worksheet:
                Deg.    Min.
Sc              40      41.7
Sa              40      42.8
Mc              30      41.7
Ma              29      53.2
Moon R&P                48.50
S R&P                   -1.06
Moon aSD                15.88
Da              99      4.2
D               98      23.6
D1              97      55.9
D2              98      26.9

GMT Obs 18:53:40

4) George also requested additional series of lunar distances. I will
submit a separate email with a Feb. 24 set of distances off Jupiter
along with my results.

Regards,
Arthur

   

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