Online celestial navigation courses?

[Lazy1]

Ironically, this morning on CBS Face the Nation they took turns making predictions of the coming year or two and their national security corespondent predicted a "probably" short term disruption of GPS or some other technology by a hostile country, he seemed to lean toward GPS in a space race context.
Made me wonder if a GPS device should not be your only backup to your GPS device.

[SeanPatrick]

Originally Posted by Breaking Waves

On one of our voyages (back in the ‘80s) we were stopping close to a place where a Cook made ”famous” lunar measurement. And I wanted to replicate it when there. It was challenging figuring out how to, as everyone had stopped publishing the lunar tables, and google did not exist yet. Looking at google today it will be much easier to get instructions, but still an excellent final test of comprehension.

There are tables available today. There is also Frank Reed's page describing how to do the whole process with a cheap scientific calculator. He also has a page which will do all the work for you ... but what fun is that?


I usually use the scientific calculator method - but I do also have the tables and have occasionally used them.

[SeanPatrick]

Originally Posted by Lazy1

Ironically, this morning on CBS Face the Nation they took turns making predictions of the coming year or two and their national security corespondent predicted a "probably" short term disruption of GPS or some other technology by a hostile country, he seemed to lean toward GPS in a space race context.
Made me wonder if a GPS device should not be your only backup to your GPS device.

Frank Reed also has an app to detect GPS spoofing/errors.


He's a busy guy!

[Dirk01]

Follow too ;-)

[kish]

This is an excellent site
Navigator Software


This website is a collection of celestial navigation resources, accumulated since 1996

• 4 navigation apps for desktop computers, phones and tablets
• 2 online web services: star finder and online almanac
• 5 do-it-yourself sextant projects and instructables
• Nautical Almanacs in PDF format
• Celestial navigation texts and tutorials
• Navigator Software
  

[dcstrng]

Originally Posted by Lazy1

Made me wonder if a GPS device should not be your only backup to your GPS device.

I'm not much of an alarmist, but I've sort of wondered similarly -- or at least, should have another skill/method for the day my GPS dies (or I drop it overboard...)

[tkeithlu]

"Celestial Navigation for Yachtsmen" by Mary Blewitt really scores with me. Aside from being very clear, she explained the concepts using geometry and simple earth figures. No trigonometry. That makes it very easy to visualize just what each term means. I never thought that spherical geometry could be so easy.

Odd side note: No one seems to have realized that on a plotting sheet compass rose, lines of longitude can be drawn for your latitude by simply aligning your straight edge with the degrees latitude on the sides of the rose. That's the scale for the cosine of the latitude.

[SeanPatrick]

Originally Posted by tkeithlu

Odd side note: No one seems to have realized that on a plotting sheet compass rose, lines of longitude can be drawn for your latitude by simply aligning your straight edge with the degrees latitude on the sides of the rose. That's the scale for the cosine of the latitude.

Here's a gif I made explaining how to make your own plotting sheets:

[MickMeck]

Originally Posted by wizoc

Try maryland school of sailing. Tom does a course which includes some video classrooms

I have passed this course from Maryland School of Sailing and recommend it. When I took the class there were many folks from countries all over the world.

Navigation Classes Online

[MikeRyan]

As a former navy parol plane commander (and, of course navigator, all navy pilots do their own navigation), I recommend the excellent small book, "How to Navigate with HO 249". Everything you need is in there.

[CaptBobR]

I sold my USCG approved school in 2015. We taught celestial. In doing the research for the course creation, my team decided the Ageton method done on a scientific calculator was the fastest and easiest to learn. We had used Starpath but if the batteries go dead, you lose the program. Using either almanac on a small craft is kind of iffy. I also found for trans- Atlantic crossings a noon site (one of the easiest to do)was sufficient

[sailorladd]

When I was learning celestial navigation, I found a gem of a book by Mary Blewett entitled celestial navigation, and if you can combine that with Frank Robb's "The form" which is a step by step formula on taking sun shots (or any heavenly body) and the steps of the maths to arrive at a LOP...(Line Of Position), 2 or 3 of these gives you a good fix... I did all my navigation with this form...and really learned from Mary's book... Good luck.

[Rainbow48]

Take a look at the online website called “TeaCup Navigation”. Very simple explanations with downloadable navigation program. The Ageton system is also good, but is easier to screw up the solution if you get the numbers wrong. Bottom line for celestial : offshore cruisers ought to be able to use it. You’ll find that the hardest part is getting the actual shot. I use the sun, exclusively.

[Captgps]

Originally Posted by tkeithlu

Do any celestial navigation users on the forum have advice regarding online celestial nav courses?

I recently lucked into an unused 1946 US Maritime Commission sextant. No index error, hasn't been dropped. Freighter level, not fancy Navy level, but sturdy and good for me. The math kicked my butt until I took Vanderbilt University's basic course, but I need more. What can you recommend for learning celestrial, given I'm not near a class therein?

I was lucky to learn on board a tanker in Australia where as a seaman I could take my 2nd Mates ticket when sufficient seatime was logged and understudy period logged also, outside of my watch hours- made for a long day!
I learned long hand with Nories Tables, quickly discovered the use of 249, selected stars manual.
A proforma can be found in many textbooks.
By doing calculations manually using cosines etc an understanding of the principles will gradually make sense.
It is spherical trigonometry!
I found the ships sextants to be quite basic and difficult to find stars with.
I bought a Plath in 1984 which had a seperate scope for stars and with the sextant preset using info from the 249 tables most stars popped up immediately which they had not always done with the trusty Kelvin Hughes 1970’s models on board.
I only used celestial as the primary navigation method on a yacht crossing from Australia to New Zealand.
Stars were difficult so a sun sight with meridian altitude gave a midday fix and dead reckoning in between got us there.

[seabum]

I think the David Burch recommendation that you got earlier is the same thing, but here is the url for Starpath's courses:
https://www.starpath.com/catalog/cou...rses_index.htm
David Burch's school, Starpath, is awesome - information is clear and complete. I feel that what Mr. Burch has is a strong teacher intuition - he really wants to help people learn. Therefore his instruction - books, courses, etc.- are extremely helpful. Good luck!