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Jeremy, you wrote:
"I first studied it at home in high school.  My father, for some reason, had
a copy of Vol 1 of Bowditch (1984 ed) and I read parts of it in high
school."

This seems to be the story for a lot of us. Bowditch was sitting on the
shelf. It looked pretty darn cool. Bit of a shame it's not a better
textbook, but that was never its purpose, of course.

"A year later I was a student at Massachusetts Maritime Academy where my
real education began.  I still was a bit of an anomaly, as before my time as
a cadet was over, I had done a sea tour, with a very heavy Celnav component
with the Texas A&M Maritime program as well."

Interesting. Thanks for the story!

You wrote:
"My captain is ambivalent to my using the sextant. He doesn't bother me
about it, as I have sailed under him for several years and he knows that I
will not let sights interfere with the safe navigation of the vessel."

That's really great. Do you yourself know any other folks working in similar
circumstances (on commercial vessels) who actively practice celestial?
Before I forget, let's talk hardware: what model sextant do you have?

I asked you:
"if you've already looked at the GPS output, why shoot the Sun at all
(except for pleasure and practice, of course)? "

And you replied:
"An old adage 'A prudent navigator uses all available means to fix his
position at sea.'"

Sure, and a fine adage it is! I guess what I meant was, if you're using the
GPS to get the longitude and from that calculate the exact moment of LAN to
take a latitude sight, doesn't that defeat the purpose? Presumably, a
reasonable excuse for doing celestial is to have an "independent" fix. If I
think of celestial sights as insurance against the possibility, however
unlikely, that the GPS might go wacky, then I think I would want to keep the
celestial sights "insulated" as much as possible from any GPS numbers.

Thanks for the info on the USCG licensing requirements. That's fascinating.
You mentioned:
"Latitude by ex-meridian at lower transit of Acrux."

Yeah, that's a great one.

You wrote:
"The only good thing is that since I took my 2nd mate's exam, they have
eliminated all moon sights and reductions.  Those were always a challenge."

NavList member Robert Eno will be pleased to hear that. ;-)

"I wonder if you are talking about what I call a Longitude by chronometer
sight.  It is taken around 8 m or 6 PM and with a relatively simple formula
that is accurate only when the celestial triangle is broad, you can
determine longitude."

Yes. Modern texts usually refer to it as a "time sight". In the 19th century
it was typically called "longitude by chronomter" but that seems a bit
ambiguous today. It's rather amazing how many vessels, especially commercial
vessels, even in the 1940s did these "pure" longitude sights. The "New
Navigation" had still not completely won out even then.

Regarding getting lat and lon by sights around noon, you wrote:
"I am going to try it using your other post's instructions and see how I
do."

There's some more detail. I had to dig up another old post for reference a
few minutes ago. Here's my first write-up on the topic from three years ago:
http://fer3.com/arc/m2.aspx?i=024178&y=200506

By the way, have you ever considered the general problem of taking a series
of Sun sights in relatively rapid succession (at an arbitrary time of day,
not necessarily around noon)? For example, suppose it's 1500 local time. If
I take ten sights over half an hour, what kind of position fix can I get?
This is a generalization of the "sights around noon" problem. There's no
easy graphical solution but it's similar in other respects.

You wrote:
"I went to camp at the seaport in the late 80's. "

Aha, so you've been sea-going for quite a long time. Did you ever get dunked
by one of those little Dyer Dhows? Of course, now I can estimate your age.
Somewhere between 30 and 35? I'll guess 32. Am I close?? :-) That makes you
a bona-fide 'kid' by NavList's statistics.

The last summer during the 80s that I was working at Mystic Seaport
full-time was '85, when I was fresh out of college (Sue Howell was lost at
sea in the sinking of the sail-training ship Marques in June, 1985 so they
needed extra help --read "Tall Ships Down" by Dan Parrot if this story is
unfamiliar). I did navigation shows at the planetarium for the Conrad
program that year, but I guess that would have been before your time there.

 -FER



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