Celestial nav - self help

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bbg

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I'd like to learn celestial navigation, but don't need a certificate. There are a lot of books on Amazon that seem to be "How to learn celestial nav", but I'd like some recommendations.

Can anyone recommend a book to help me self-learn celestial navigation?

Also, what else will I need? Sextant obviously, but what else?

Thanks in advance.
 
No one book covers the lot - as in any other subject.

Try :

1. Ocean Sailing - Tom Cunliffe ( better than his first book Celestial Nav.) Probably the best and clearest introduction to the black art.

2. Ocean Navigator - Kenneth Wilkes

by the time you have digested these two you will be ready for the classic :

3. Celestial Navigation for Yachtsmen - Mary Blewitt

Good luck - it is a fascinating area of study, still an art rather than a science.....

later edit :

You will also need the following :

Nautical Almanac - get the american 'Commercial' edition - cheaper than the government ones.

Sight Reduction Tables - again the USA 'Celestaire' commercial edition is smaller and cheaper - there are 3 vols.
Note there are mistakes in vol 2 which are to be corrected later in the year, Vol 1 only lasts for 5 years.
The above SRT's and almanac are available online and also have the Vol 2 errors.

Plotting sheets are a good idea and here the situation is reversed, for me the 'official' ones are superior to the 'commercial' ones.
 
I am a huge fan of "Celestial Navigation in a Nutshell" by Hewitt Schlereth. ISBN 1-57409-058-5. Excellent value from Barnes & Noble at $13.95. Most of my students finish up buying it.

Having said that there is more than enough guidance on the internet, including complete astro courses. http://www.celestialnavigation.net/ is a good starting point.
 
" Nothing initially. The book contains practice tables and observation data."

Good point...

bbg - you could add a 5" Douglas protractor to your shopping list

and a 0.5mm propelling pencil with 2B leads will give you more accuracy then the usual standard pencil..
 
Once you have some idea of the theory and practice, you might take a look at "The Complete On Board Celestial Navigator" by George Bennett. This contains a long term Almanac and very easy to use sight reduction tables in compact form. As an ex-professional navigator with the cosine haversine formula etched into my brain, memories of 5 figure logs, inspection tables like AP3270 and a whole shelf of "quick" methods with many complicated rules to remember, I would recommend this publication.
It is available from Amazon, Waterstones and many other sources. No commercial connection!

Half the fun of being a navigator in the pre-GPS Merchant Navy was the Astro - there weren't any alternatives. It's now amateur sailors who will keep this ancient and satisfying art alive.
Good luck!
 
I'm going through the self-teach route at the moment.

I've been using the George Bennett book, from personal recommendation. It's a very useful book, and does contain all the tables you'll need. Once you've got the hang of it, very easy to use.

It does take some work to understand. The only real annoyance is that one of the tables of differences doesn't have a sign for one of the factors, but the text rather glosses over the fact you need to work it out. No problem once you've twigged, but it took me longer than it should to realise!

One tip - from land, with no horizon, you can get the elevation of the sun with the aid of a bowl of water - bring the sun down to meet it's reflection, then halve the angle. You'd need to monkey about with the Sun Correction, as Bennet's book includes the semidiameter correction with refraction and parallax corrections in one handy table.

Really useful tip for self-learn: The method used in Bennet's book is to go through a procedure to work out what the elevation of the Sun should be from a given location. You then compare that with the observed altitude. But there's plenty to go wrong in the calculation. Download Stellarium - PC planetarium software. Plug in the coordinates of your assumed position and the date/time, and it will tell you the altitude of the Sun. The altitude calculated by Stellarium should be exactly the same as the altitude you worked out from the tables. This is a good way to make sure you've understood the method correctly - I found two errors in my calculations (including the wrong sign for one of the corrections, and a really stupid systematic error where I was using the wrong figures).

As an aside, I found his proformas not to my liking. I spent some time devising my own, and found this helped me understand the process better, as well as giving me forms that I prefer. But that probably depends on your learning style.

Oh and I bought the cheapest sextant I could find - a secondhand Davis Mk 3 - good enough to get me within 12 miles on first sight (OK, on land). The instruction leaflet is a masterpiece; just 14 pages of A5 tell you how to adjust & use the sextant, how to calculate your lat & long by meridian passage, hand ow to calculate lat by star sight of Polaris.

Hope that helps
 
As "Onenyala" has it, Nicholls Concise Guide, is the tome for celestial navigators. Hell of a price now at around £80., but I saw one last week in the local second hand book shop for a tenner.
 
I've just done this on a transatlantic crossing

I used books by Blewitt and Cunliffe as others have suggested.

Obviously you want to make sure you can reduce the sights on paper happily - but to be honest once you are happy you can do this I used a laptop as it let me take many more sights and check how I was doing and get practice in on the actual sight taking and identification of stars etc rather than spend all teh time in a book of tables. So fairly quickly worked out what was a good fix or not !

I liked this - very cheap - shows sky and allows you to plot sights:

http://www.nomadelectronics.com/PC/PocketStars/default.aspx

There are a range of others
 
Ah - Nicholls Concise Guide....
I never liked any of Brown, Son and Ferguson's publications, although they were everywhere at sea and in Nautical Colleges. They always seemed so antiquated in content and typeface. Same goes for Norie's Tables. Far, far better are the Admiralty Manuals or the American Practical Navigator, or Dutton's Navigation and Piloting (also American).
 
I agree - learn how to use the book and a plotting sheet, then probably OK to concentrate on technique and use a calculator/laptop, which is what I would do now if I was taking a lot of sights. I would always carry the book as a backup, though.

I also have a copy of Pocket Stars which runs quite happily on my elderly PDA.

Good to see a lot of ongoing interest in all this!
 
Thanks to all. The link from Scruff is very useful too, but the author makes the same mistake as in the book that was criticised.
 
Unless you really want it *right now*, there might be another book to consider, because the RYA's Astro Navigation Handbook is due to be published sometime in the next two or three months. It's already on Amazon's website , but I know it hasn't been printed yet because the final page proofs are spread all over my dining room table!

It's intended to be as easy to read as it can be, without skimping on facts or accuracy -- and being RYA, the text was "peer reviewed" long before it got as far as page proofs.
As well as a "how to do it" book, you will need a sextant, a decent watch, an almanac, a set of sight reduction tables, some plotting sheets, and ordinary chartwork weapons.

The chinese are making some good metal sextants (like the Astra 3B) which are so "cheap" that it's hardly worth bothering with a plastic one.

A £5 watch from your local garage is probably a better timekeeper than Harrison's chronometer.

Reeds do an astro almanac that will serve most yotties better than the bulky and expensive official version.

Sight reduction tables (get the Air navigation version) can be picked up second hand from the likes of Warsash Nautical Bookshop. There are three volumes, of which you need V2 and/or V3 depending where you are going to be operating. V1 is the only one that goes out of date (it officially lasts ten years, from 2000 to 2010, but you can squeeze a few more from it, and anyway you only need it if you are going to do star sights.

And you can make your own plotting sheets or use any chart that covers the right latitude.

Bon chance!
 
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