Celestial Navigation and the Sextant, Part II

Forrest Brownell (forrest@slic.com)
Sat, 09 Jan 1999 10:58:41 -0500


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West Wight Potter Website at URL
http://www.lesbois.com/wwpotter/
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Jerry Menzies' recent letter ("Re: Book - Longitude (sextant?)")
points up a glaring omission in my earlier note concerning the methods
of celestial navigation. Though star sights are of little or no value
in "practical" small boat navigation, the prospective navigator will
still want to get to know the navigational stars. I've found two
books particularly helpful in this regard:

o _A Field Guide to the Stars and Planets_, by Donald H. Menzel. (A
Peterson Field Guide.).

Get the 1964 edition, if you can (you'll have to find it in a
secondhand bookstore). The "sky maps" are the most valuable part of
the book, and those in later editions -- written in collaboration
with J.M. Pasachoff -- do _not_ identify all the navigational stars.
Newer isn't always better!

o _Leslie Peltier's Guide to the Stars_, by (surprise) Leslie C.
Peltier, recently reissued under the title _The Binocular
Stargazer_.

This narrative tour of the night sky though the seasons was written
by an indefatigable amateur whose fascination with the heavens led
him to compile some 130,000 observations of variable stars over a
span of sixty-odd years, discovering twelve "new" comets and four
novae along the way. Peltier's book is also a useful reminder of
how much can be done with the simplest equipment. He owned only two
pairs of binoculars in his life: his first were 8x25 compacts; much
later, he acquired a 7x35 wide-angle pair. Neither was what today's
"experts" would recommend for binocular astronomy or bird-watching
-- Peltier's other interest -- but this fact seems not to have
handicapped him in the least.

And I'd also echo Jerry's other recommendation. If you get the
chance, don't miss the BBC-WGBH dramatization of John Harrison's
struggle to have his chronometer accepted by the Board of Longitude.
Though it owes more to Harrison's own journals and Patrick Malahide's
superb acting than to Dava Sobel's book, it's an affecting account of
the life of a brilliant and difficult man.

Oh, yes -- I almost forgot. Rejoice! The Naval Academy has not, in
fact, eliminated instruction in celestial navigation from it's
curriculum, though the syllabus has been somewhat curtailed. The
initial proposal met with a storm of protest from Naval officers, both
serving and retired, and was subsequently withdrawn.

Forrest Brownell
South Colton NY