Celestial Navigation

[Talbot]

Celestial Navigation can be as complex or as simple as you want to make it. Total understanding of why we add different corretions is nice to have, just as being able to do the calculations using Haversines etc like they did in Nelson's day.

However, they are not essential to being able to find your position.

Tom Cunliffes book shows the minimum necessary to be able to do just that

[SkiprJohn]

Aloha Zach,
As posted a few back most books I've read contain the same information. I'm not familiar with the one you mention but if it easy for you to understand then it will be a good book. My way of "do-it-yourself" in all aspects of life is that I buy 3 books and pick out the one that explains my project in the simplest but detailed manner and go with that one.
I don't buy new books. I shop at used book stores or yard/tag/garage sales.
Some books touted as celestial navigation deal with calculators or other electronic devices. I don't read those books but go with the more traditional methods using the Nautical Almanac and Sight Reduction Tables for Air Navigation (H. O. 249).
The meridian passage or noon sight which Talbot and I have been talking about only requires a sextant, a watch, the Nautical Almanac and a good form to fill out.
If "Practical Celestial Navigation" covers the concept of determining latitude and an approximate longitude by means of a noon sight/meridian passage then it will be a useable book.
I'll be looking for Tom Cunliffe's book as recommended by Talbot but my selection here on an island is a bit limited. Maybe I can find it used on Amazon.com. Good luck and--
Kind Regards, --John--

[Talbot]

Dont know about Amazon, but its £8.95 from the RYA. for his Celestial Navigation.

[Vasco]

Talbot,

I used the haversine method when I went to sea and I assure you it wasn't in Nelson's days as I think I'm still alive. We were not allowed to use any shortcuts such as HO 249. We were required to know the principles of navigation rather than "filling in the blanks" in a form. Why, I don't know except that traditionally, that was the way it was. I hated spherical trigonometry having flunked math most of my school days. The hardest part of navigation is bringing a body down to the horizon especially in a small sailboat. The rest is just "filling in the blanks" if you've got the right forms.

[mike d.]

this is a very interesting/good post. so glad to here people still believe in the use of sextants ect. i will be learning how to use one myself for when we go off in a 1yr or 2. SkipJohn thnks for the book info i already have two that my dad says are really good, but for me a little intimidating. Dad was a capt for Ned-Loydd in the 50s and i inherited his sextant. he tried to show how to use it when i was young but you know how kids are.

regards to all! Mike
remember sail fast-live slow

[SkiprJohn]

Aloha Mike,
Ask any questions here and you're certain to get answers. If you inherited a sextant from a Captain (your father) it is bound to be a good one. It would be nice and honor his memory to learn to use it. Vasco made a point. Celestial can be intimidating if you try to learn the really hard way.
Regards, --John--

[Talbot]

Mike, part of learning how to use a sextant is removing the errors that are inherent in any sextant. The book that I referred to above (Clestial Navigation by Tom Cunliffe provides the best description of these errors and how to remove them, that I have ever read.

I also inherited my fathers sextant (used during the second world war), and will soon need to get the mirrors re-silvered. luckily there is a company near me that specialise in this area.

[SkiprJohn]

Aloha All,
Last Friday night I conducted my second class in "an Introduction to Celestial Navigation." I find it very interesting that folks still want to learn this even though GPS has really taken all the "fun" out of celestial navigation. It took us 3 hours to walk through the steps to find ourselves. It would have taken 5 minutes or less using GPS.
I teach it because people want to learn and at the cost of $3.00 it is affordable to them. All I do is walk people through a Meridian Passage/Noon Sight equation and how to use a sextant. I don't expect anyone to come out of the class really ready to do a circumnavigation. I really do expect everyone to start really appreciating the GPS, which they do.
As an old sailor I would hope that everyone would have a bit of curiosity concerning the "old way" of finding their way around the oceans. Its certainly not necessary and takes a lot of time but in case of power failure in a life raft, might help.
Kind Regards,
JohnL

[TonyQ]

well I use an old davis plastic sextant , I'm always 5 miles out and I know I'm always 5 miles out so the care factor lies , I'm 5 miles out ,,

[clausont]

I am just now starting to learn celestial navigation. After reading everything in this thread, I have a few direct questions. I had planned on buying a couple of books (much as SkiprJohn has said that he does when learning something new), sight reduction tables and a Nautical almanac. After looking for the last two items, I find that there are enough choices that I am having a hard time deciding exactly which to look for.
My question: Which books, sight reduction tables and nautical almanac would you recommend for an absolute beginner?
I do not know anybody in this area that knows celestial navigation that I can go to for help when I get stuck, so I think that good, easy to understand books will be important.

[btrayfors]

One of the simplest books is "Celestial Navigation for Yachtsmen" by Mary Blewitt. It's widely available in most any bookstore.

As for the Nautical Almanac, be sure to get either the genuine US Government pub, or one of the commercial versions of it. NOTE: the widely popular Reeds Nautical Almanac no longer contains almanac data. It's title, therefore, is very deceptive (and they don't care...I talked to a rep about this at the Boat Show in Annapolis).

As for the sight reduction tables, most sailors prefer HO 229 or HO 249. I'm one who prefers HO 214. Any of these will do fine...it's just what you get used to.

If you'll shoot me an email to: bill at wdsg dot com

I'll be happy to send you some forms I've worked up for sight reduction. It would be good to start with the very useful Noon Sight for Latitude, then the Noon Sight for both latitude and longitude.

Congratulations both on your desire to learn celestial nav, and on your determination to go with "too small a boat". It's the going which is important, not the size of the boat :-)

Also, be sure to check out: Celestial Navigation Net

Bill

[hellosailor]

Blewitt's book is the classic for "well, now that we're in the lifeboat, who's going to learn how to use the sextant today?!" It is eminently practical, simple, to the point.

For a bigger picture of navigation and the role of hte sextant in it, I'd suggest George Mixter's Primer of Navigation which basically covers the entire field, piece by piece, with equal clarity explaining how and why things have come about and work. A much longer but very enjoyable text.

And for the simple mechanics of "But am I doing this right?" Bill Buckley's video on basic sextant use, which walks you through using the sextant and running calculations with the tables.

Speaking of which...I know purists want to stick to paper tables, but having a sight reduction program on a dedicated calculator, or on a Palm (reliable, inexpensive) or a laptop means that you can double-check against your own math errors or just get a nice fast sight reduction.

[alan2]

Originally Posted by SkiprJohn

Aloha All,

I am coming up with a really good noon sight form that anyone can use with a Nautical Almanac to find latitude and longitude. Let me know if you are interested and I'll make it available to forum members.
Kind Regards, --John--
Book Recommendation - Celestial Navigation by H. O. 249 - John E. Milligan

Re the above, excerpted from your post, I would like to see the form you mention.
Thanks.
alan2

[TimoVilla]

Dear John,
I did my celestial navigation course in Finland during 2003-2004 and found it really interesting.
However, an old friend of mine, professional skipper and sailor, told me that his friends used to ask him what they needed to have on a long voyage and he used to give this answer: "take a bag of gps's, some hand held too, an other bag of batteries for them, and keep the bags separtely, on a safe and dry place on your boat".
An other finnish skipper i happen to know, and who did his world around voyage 1993-1997, told me that celestial navigation skills are good and nice to have but just for fun and a nice way to spend some time on voyage.

best regards,
timo
p.s.
my celestial navigation instructor used also forms for everything

[SkiprJohn]

Aloha Timo,
GPS is very convenient, well respected and, so far, very dependable. I guess I keep my celestial skills up just for the mental exercise and in the eventuality that satellites stop working.
Good to hear from you.
Kind regards,
JohnL