Celestial nav - self help

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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 V1 is the only one that goes out of date (it officially lasts ten years, from 2000 to 2010, but you can squeeze a few more from it, and anyway you only need it if you are going to do star sights.

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These "inspection" tables are excellent and were in use in all the ships I sailed in - opened up on a comparatively huge chart table. Even 2 volumes are very bulky to stow and would be awkward to use on the average yacht. It is possible to get photographically reduced versions, but the print is then too small (for my eyes, anyway).
Pages can be downloaded free on the web, but it's just more hassle IMO.
 
If any of you would like some step-by-step forms for reducing your sights, send a pm to me with your email address and I will send them to you. They tackle the problem in a mechanistic way, but once you have the concept in your head, the exercise of reduction will take you a mere 20 minutes, if that! Meridian passage, even less.

Sticky
 
Each volume of the air sight reduction tables is about half an inch wider and a quarter of an inch taller than a typical magazine, and about twice as thick.
I lived for several seasons with all three volumes and a Nautical almanac under my mattress -- and I much preferred to do the arithmetic on the saloon table!
 
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Do you want "to learn it", or simply work out your position?

The latter can be easily done using Cunliffe + proforma's.

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I am considering doing the MiniTransat in a couple of years. One of the requirements is a 1,000 nm solo qualification sail (on a specific course). As part of the qualification, one must provide two CN position plots, including showing all workings.

I really just want to be able to fulfil that requirement. I want to really learn it, and be able to do it right, but don't feel the need to be a torch-bearer for those who want to keep CN alive. I don't need to know all the ins and outs, arcane details etc. If I can fulfil the requirements by taking two sun sights on successive days, that is all I would like to do.
 
I want to really learn it, and be able to do it right, but don't feel the need to be a torch-bearer for those who want to keep CN alive.
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That is a situation similar to many doing the RYA Astro course.

Most come off these courses, if 5 days 'intensive', partly brain dead & only with difficulty able to tackle the sight reductions, struggling with the 'simple' arithmetic involved, struggling to remember where they get the information from & then plotting the results.

In most of the courses I have run, Cunliffe has proved to be a very 'easy' to follow primer. This together with good pro-forma's/including plotting sheets (all essential/useful aide memoires), should work for you. Only after using these techniques for some time, does it 'sink in' & you start to really understand it.

I take my hat off to anyone able to use a sextant on a 22' minitransat - best of luck!
 
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Can anyone recommend a book to help me self-learn celestial navigation?

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Ocean Sailing: Celestial Navigation, Weather, Passage Planning by Tom Cunliff

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

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Nothing initially. The book contains practice tables and observation data.

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It's a great book, which made no sense until I'd learnt enough to realise that there is a typo on page 42. It refers you to the table on page 35 but it should have been the table on page 38.

Once that was realised ( I woke up at 0510 wrestling with the concept!) the rest made good sense.

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Duncan

That's well spotted.. I had missed that for a good few years !!

It isn't 'the bookmark' either which is indeed page 35.

Thanks for that

sh
 
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