Re: [Paddlewise] Celestial navigation

In a message dated 98-09-11 05:34:55 EDT, dave_at_seacanoe.com writes:

<< Does anyone have any recommendations on celestial navigation videos and/or
 books?  I'd like very easy-to-learn stuff as I've read some on the subject
 without understanding a lot of it. >>

There is a well recommended book , I think it may be called just "Celestial
Navigation" and the author is (if memory serves?) Mary Blewitt.  However, I
don't think there is any really easy way to understand the theory behind
Celestial Navigation.  It is however easy to use, if you don't do the math
from first principles and if you use modern calculator/computer power instead.
You can either use a special hanheld calculator (Celesticomp - costing about
$450....ouch!) or a notebook computer if you have one anyway, or a
programmable scientific calculator ($75 maybe?).  The actual process of taking
a star/sun/moon/planet sight with the sextant & keying in data to the
calculator can be learned very easily without understanding any of the
underlying theory, (but a more thorough understanding is good for the soul
anyway)

My question, however, is why would you want celestial navigation in a kayak?
You would need a heavy & bulky sextant, and position accuracy is not suitable
for coastal work anyway - more for open ocean stuff.  I just finished earlier
this year a US Power Squadron Celestial Navigation course (a lot of work, but
worth doing) and accuracy of our sights had to be +/- 5 nm - not very
applicable to kayaking, I think.  A GPS is a much easier & cheaper solution -
and takes less space on board.  If I were sailing to Bermuda, I would want to
use celestial nav to practice the procedure, but I would have a GPS along too,
to check my skill.  In effect the sextant nowadays is used by most sailors as
a backup in case their GPS fails (lightning strikes or whatever) but in order
to get good results with a sextant practice is probably advisable.  

I suggest the BEST approach to knowing where you are is to learn conventional
navigation (US Power Squadron offers a series of excellent courses on this
subject) with chart, compass, plotting tools, etc.  If the GPS fails (& it
will!) you will still be able to get where you need to go, providing you have
a chart & compass.

best regards

David Booth
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