I've always wanted to learn how to use a sextant. That would be pretty cool!!

I wonder how accurate they are?

Ken

Depends on the sextant itself, the person using it and the conditions under which it is being used. A good sextant, used by someone with skills and familiar with that sextant and under good conditions (flat seas, with a clear horizon and a clear sky) can result in some good fixes.

The actual use of the sextant is only a small part of getting a fix. You need to be able to do that math, which means, IIRC, you need at least two publications: an almanac to tell you which celestial bodies you are looking it and how to correct your height observed for the bodies observed (http://celestaire.com/catalog/products/2009.html), and a table like H.O. 229 (http://celestaire.com/catalog/products/5902CE.html) or H.O. 249 (http://celestaire.com/catalog/products/5907CE.html). It's been more than 20 years since I actually did the math or obtained a fix, so my memory might be a little off.

If you are on land, using landmarks is almost always more natural and effective. Also, it can be pretty tough to get the right horizon on land. You would either need a sextant with an artificial horizon built in, and I recall hearing that such things are made, or guess at the level at which the horizon might be, which is probably going to reduce your accuracy.

I have my dad's WWII sextant, manuals, etc. from his air force navigator days...he tried to teach me several times when I was a young sprout but I wasn't interested. Now that I am interested and want to learn, he is gone. We never appreciate something or someone so much as when we no longer have it/him.
I have purchased a book and video of Wm F Buckley's Celestial Navigation Made Simple (yeah, right) along with several other guides and hope to learn a little something.

we can talk about CelNav, Jackie. I used CelNav in the 80's.

Folks, there are myriad ways to do navigation. For those living close enough to a US coastline, Loran C is available and can be used in the greater Puget Sound Region, New York Metro, DC, New Orleans, Miami, Houston, LA, San Francisco, just to name a few. Orienting the Loran output to a land map is no longer an issue. Then there are all sorts of terrestrial beaconing systems at our disposal. You just need the tech to tap into them. Back in the 80s we put together an entire network that we could find any metro bus anywhere in King or Pierce County using nothing more than an array of terrestrial beacons we put up ourselves. It wouldn't be that hard to tap into that sort of technology these days. It wouldn't be too hard or expensive to do the same with a set of community repeaters and a df kit for that matter.

As far as celestial nav goes, isn't number crunching what we got these wonderful machines for? I am sure there are already optical input devices that make celestial nav using a laptop pretty much an exact science. I just bet with the right video input a good program could compensate for all sorts of variables enough to give you a true fix.

We set up a laser nav system one time using two different colored lasers set parallel from two known fixed locations overlooking a city. From anywhere in town you could see both beams, you could fairly easily calculate your location relative to the points of origin. We figured that was good for at least 100 square miles.

I guess I can't just use the North Star, right?

Sue

It is a good place to start. If you live anywhere urban, the North Star is a dim star and nearly impossible to see due to all the ground lights.

You kind of have to guess where it is by sighting a line between the more easily observed Big Dipper and Cassiopeia constellations.

It is also really difficult to see if you are somewhere in the southern hemisphere.

Here are some good references for learning navigation without GPS, or even map and compass. It is also fun to practice.

Emergency Navigation, 2nd Edition (Paperback)
by David Burch (Author)
International Marine/Ragged Mountain Press; 2 edition (June 20, 2008)
# ISBN-10: 0071481842
# ISBN-13: 978-0071481847


Emergency Navigation Card (Cards)
by David Burch (Author)
Paradise Cay Publications (June 2000)
# ISBN-10: 0939837587
# ISBN-13: 978-0939837588


The Lo-Tech Navigator (Paperback)
by Tony Crowley (Author)
Sheridan House (July 31, 2004)
# ISBN-10: 1574091913
# ISBN-13: 978-1574091915


Finding Your Way Without Map or Compass (Paperback)
by Harold Gatty (Author)
Dover Publications (March 19, 1999)
# ISBN-10: 048640613X
# ISBN-13: 978-0486406138