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Old 05-12-2015, 15:18   #46
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Re: How to do celestial today

have to applaud your intent - I try to keep some skills with the sextant - I download and print the almanac tables for a few days around a good testing period so i can do a completely paper based process - the only differences are (1) i dont buy an almanac anymore, and (b) I do use the GPS to check my accuracy (usually a bit depressing) and (c) because the GPS is the most accurate timepiece on board I use it for timing sights - dont keep a proper timepiece aboard anymore - which does tend to undermine the whole thing. I bear in mind that latitude navigation is a pretty satisfactory and simple emergency procedure.
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Old 05-12-2015, 20:05   #47
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Re: How to do celestial today

Quote:
Originally Posted by charliehows View Post
have to applaud your intent - I try to keep some skills with the sextant - I download and print the almanac tables for a few days around a good testing period so i can do a completely paper based process - the only differences are (1) i dont buy an almanac anymore, and (b) I do use the GPS to check my accuracy (usually a bit depressing) and (c) because the GPS is the most accurate timepiece on board I use it for timing sights - dont keep a proper timepiece aboard anymore - which does tend to undermine the whole thing. I bear in mind that latitude navigation is a pretty satisfactory and simple emergency procedure.

Make your life sort of easy; just use

TABLE 4- GHA and Declination of the Sun for the Years 1981 to 2025 (Extended)

Get it here;

http://thenauticalalmanac.com/TABLE%...xtended%29.pdf

If you want to do star sights use this;

TABLE 4- Long Term GHA Aries

Get it here;

http://thenauticalalmanac.com/GHA%20...0to%202019.pdf


You can get the 57 Navigational Stars SHA & dec for 2015 here;

http://thenauticalalmanac.com/2015%2...%20&%20Dec.pdf


You can get the 57 Navigational Stars SHA & dec for 2016 here;

http://thenauticalalmanac.com/2016%2...%20&%20Dec.pdf
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Old 04-01-2016, 10:50   #48
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Re: How to do celestial today

I obviously use GPS as my primary nav source but I still do celestial when on a passage. It gives me something to do and forces me to keep up good DR discipline.

I use two resources, an iPad app called ezAlmanacPro which has all the daily, conversion, correction and reduction tables as well as a calculator which automatically does the sight reduction. In fact, in a pinch, you could even use the iPad or iPhone itself to do an actual sight or running fix.

The other is a single little book of 100 pages from which, with a few extra steps, you can correct and reduce a sight. It is called the Long Term Almanac 2000-2050 by Geoffrey Kolbe. Available on Amazon for less than 25 bucks. This book, a sextant and a few Universal Plotting Sheets is all you need.

Long Term Almanac 2000-2050: For the Sun and Selected Stars With Concise Sight Reduction Tables, 2nd Edition: Geoffrey Kolbe: 9780914025108: Amazon.com: Books
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Old 30-01-2016, 12:48   #49
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Lightbulb Re: How to do celestial today

Fellow Navigators.

Years ago I developed the pictured "Nav-A-Form". as a help in putting down all those figures and notes when taking sights, bearings, compass corrections, tide & current data, Determination of L.A. noon etc. as shown on the two illustrations. I placed it all on a 13"X14" ( same size as a position plotting sheet) plastic laminate that the navigator could pencil in figures that could be later be erased. One side has a graph whereby one can plot a string of sights and determine which one or two is good for reduction. At the time I thought it was a good idea but along came Loran and GPS and interest in a laborious calculations too much trouble. But I had made up numerous
Nav-A Forms which I still have.

So, is their still an interest in such an item for the navigator today ? Would it be worthwhile to try to market it again ? I checked to see if it would fit in to any available envelope ( cost alone about 3 bucks ) then the cost of shipping...etc. Or just

An Ole Salt 86 would like to know.

Thanks for any suggestions.
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Old 01-02-2016, 14:02   #50
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Re: How to do celestial today

I can warmly recommend Celestia

Celestia: Home

It is a real-time simulator of the skies (stars, planets and even satellites) that can help you brush up some forgotten knowledge of the skies. The options are vast, for example; you can overlay lines for constellations, artwork for constellations, different "sort" of constellations (Western, Inuit, Polynesian...) Click on an object and see what the distance is, how bright it is and much more. I learned quite a lot from it actually.
It works without an internet connection, and best of: it is for free (donations are appreciated)
It is however quite a demanding program, so if your PC is an old banger you might experience some slowesque skies
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Old 01-02-2016, 15:32   #51
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Re: How to do celestial today

Oooops... I made a mistake. The program is called Stellarium, not Celestia.
The correct website is: Stellarium

Sorry for any inconvenience
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