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Old 12-03-2013, 03:44   #31
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Re: Sextants and celestial navigation

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Originally Posted by Delfin View Post
I'm curious if anyone has a suggestion on celestial navigation software. My only experience with a sextant is finding Hawaii and home again a few years ago, and exclusively used dawn and dusk star sites reducing them with Merlin II on a Sharp programmable calculator. This was so simple and accurate I really regret losing the Sharp. We'll be heading back to Hawaii, hopefully year after next and would prefer to continue to use my sextant for navigation. Yes, I have GPS now, but you need something to do on long passages and celestial nav is fun. So, any recommendations from the experienced crew on this thread for software that will work as well as the Merlin software did?
If your taking a lap top, then Teacup Navigator is a reaslly good and free to download program. See
Celestial Navigation
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Old 12-03-2013, 03:49   #32
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Re: Sextants and celestial navigation

Altitude Correction Tables

For the moon corrections, you will need an almanac providing the hourly value of Horizontal Parallax (HP)

The other correction tables are for low altitude sights (below 10 degrees) and for conditions with non standard air temp and atmospheric pressure
Attached Files
File Type: pdf Additional Corrections.pdf (65.9 KB, 29 views)
File Type: pdf Low Alt Correction.pdf (68.7 KB, 24 views)
File Type: pdf Moon Page 1.pdf (96.3 KB, 29 views)
File Type: pdf Moon Page 2.pdf (94.5 KB, 25 views)
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Old 12-03-2013, 03:51   #33
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Re: Sextants and celestial navigation

Corrections for sights of Polaris (for year 2013)
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File Type: pdf Polaris Page 1.pdf (73.4 KB, 30 views)
File Type: pdf Polaris Page 2.pdf (72.5 KB, 28 views)
File Type: pdf Polaris Page 3.pdf (68.2 KB, 27 views)
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Old 12-03-2013, 04:18   #34
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Re: Sextants and celestial navigation

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the next flight to Papeete included me, my tables, my Polaroid sunnies, and my swimming togs (trunks).
Presumably you didn't need vol 3 of NP303 or much by way of thermals. I'm surprised you don't hear people complain about the *weight* of celestial nav more often. 3 volumes of tables in addition to all my winter gear always pushes the airline baggage allowance. Plastic sextants are a big win in that department
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Old 12-03-2013, 04:20   #35
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Re: Sextants and celestial navigation

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Originally Posted by muttnik View Post
Presumably you didn't need vol 3 of NP303 or much by way of thermals. I'm surprised you don't hear people complain about the *weight* of celestial nav more often. 3 volumes of tables in addition to all my winter gear always pushes the airline baggage allowance. Plastic sextants are a big win in that department
1 pair swimming trunks = 250 grams
1 pair polaroids = 100 grams
1 sextant in wooden case = 5 pounds?

Lots of weight allowance for tables

I notice he didn't pack a toothbrush
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Old 12-03-2013, 08:16   #36
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Re: Sextants and celestial navigation

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Corrections for sights of Polaris (for year 2013)

Thank you very much for this, I was looking for that everywhere, (on the internet) and thanks for that link earlier. I know about and i have that one...



i was looking for this one....



and this one....






......and for those asking for astro software. what is point then, stick to gps
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Old 12-03-2013, 08:18   #37
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Re: Sextants and celestial navigation

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1 pair swimming trunks = 250 grams

Lots of weight allowance for tables

it weight less then your swimming trunks



Not to mention that you do NOT need all of them on board. just for the area where you are sailing. even crossing Atlantic. you are not going from equator to north pole and back that you will need all of them. for crossing Atlantic you will need, let say, only one "book" if you are using marine 229
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Old 12-03-2013, 08:29   #38
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Re: Sextants and celestial navigation

The beauty of celestial is that you need no electronics or modern technology, just an accurate time piece for determining longitude. If you want to be truly independent in determining your position (which is the whole point of celestial) then you want the paper sight reduction tables and the paper almanac.
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Old 12-03-2013, 08:33   #39
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Re: Sextants and celestial navigation

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just an accurate time piece for determining longitude.
I dont even need that !!!!

Dave
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Old 12-03-2013, 08:38   #40
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Re: Sextants and celestial navigation

Then what would you use? (Other than seeing a land mass, a DR or using something that requires the use of electrons?)
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Old 12-03-2013, 08:43   #41
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Re: Sextants and celestial navigation

lunars
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Old 12-03-2013, 08:52   #42
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Re: Sextants and celestial navigation

I have only read of that. I didn't know anyone actually used it. How accurate has it been for you?
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Old 12-03-2013, 09:06   #43
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Re: Sextants and celestial navigation

For those is the US there is the United States Power Squadron (USPS) Junior Navigation and Navigation courses. JN teaches Sun sights using the Law of Cosine method. LOC uses a calculator with trig functions to calculate a LOP.

JN is a great intro to celestial and covers all the basics. It assumes that you know plotting.

Navigation takes off and teaches lunar and star sights as well as a method of sight reduction that only needs the almanac and the ability to add.

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Old 12-03-2013, 09:12   #44
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Re: Sextants and celestial navigation

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I have only read of that. I didn't know anyone actually used it. How accurate has it been for you?
Im using Bruce Starks Method, lets say my attempts are still in the 15+ minutes accuracy !!. It really shows up sextant error and sight taking procedures. It is capable of about 30 seconds accuracy ( but repeatable) but Im a long way from that !

Not yet tried in afloat with any sufficient accuracy, but working on it. The main issues is its easy to get multitude of adds and subtracts mucked up!!.

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Old 12-03-2013, 09:28   #45
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Re: Sextants and celestial navigation

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Im using Bruce Starks Method, lets say my attempts are still in the 15+ minutes accuracy !!. It really shows up sextant error and sight taking procedures. It is capable of about 30 seconds accuracy ( but repeatable) but Im a long way from that !

Not yet tried in afloat with any sufficient accuracy, but working on it. The main issues is its easy to get multitude of adds and subtracts mucked up!!.

Dave
Very cool
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