A part of my celestial navigation tool-kit.

I learned celestial nav a long long long time ago, as in way before anyone ever heard of satnav. But I was a youngster and never got proficient. And though we don’t have a chart plotter on the Far Reach, I, like most of the modern world, have come to rely on GPS because it’s quick, simple, and accurate. But…using GPS always leaves me feeling…unsatisfied. Like I cheated. It’s just too easy. There is no reward.

One of the things I have always enjoyed about sailing is in some ways (sometimes small, sometimes large) you can rub elbows with your heroes of yore—things like beating up a narrow channel, reefing the sails, executing smart tacks, changing heads’l, flaking out lines, tying knots, and dropping and weighing anchor, etc. are skills common to sailors past and present. Sailing at night or making offshore passages are more advanced skills but were also essential in an earlier era. These skills were everyday staples for Drake, Decatur, Slocum, Dumas, et.al. These common seamanship skills connect us from the present with those of the the past. But in the days before GPS, sailors also had to use the sun, stars, and planets, along with some fancy math to make it there and back if they wanted to live to tell the tale. So, while there is a never ending list of skills associated with “modern” sailing…pushing a button to determine your position is not a skill shared with sailors of the Golden Age of Sail or even the sailors of the last generation.

GPS is an incredibly important tool. I use it too. I would never denigrate it. Never. It’s like…magic. If Drake had access to it he would have used it. No doubt about it. But, that’s not the point, for me anyway.

It’s as simple as this…if you desire to really connect to those sailors that made offshore voyages before GPS; if you want to know if you can cast your eye to the heavens and determine your location as was done by countless navigators before GPS; then there is no avoiding learning the one skill we have so completely given up; the one skill that was for centuries the most essential for those sailors who were brave enough to venture over the horizon to distant lands—Celestial Navigation.

Truth be told, 35 years ago not knowing celestial navigation kept the vast majority of otherwise very capable sailors hugging the coast. Not so anymore. Anyone with a hankering to make an offshore voyage, provided they can overcome their trepidation and fear of all the things that can go wrong, can make the trip. With a chart plotter you don’t even have to know how to plot lat/long. Accurate navigation is now assured…as long as the GPS is working.

Since I had some time to kill waiting for the winds to align for the trip home to NC, I cracked the books. What does learning celestial on your own look like? Take a look:

There is some reading.
And more reading….
And still more reading…
There is some head scratching. “What the hell is sidereal time and the First Point of Aries?”

To learn it on your own takes a lot of reading. Patient reading. Reading for comprehension. Some of it is confusing. But, thoughtful persistent reading and some trial and error is the key to sorting it out.

I started by going back to the very book I used to learn how to take a noon-sight when I was 17 year old…”Self-Taught Navigation: Ten Easy Steps to Master Celestial Navigation,” by Robert Kittredge. It was printed in 1970. It was a popular book for those wanting to learn celestial navigation—and for good reason—as he insisted that it’s just not that hard.

A few years ago when I first thought about diving deeper into celestial navigation I read good reviews on “Celestial Navigation in the GPS Age,” by John Karl. I purchased it. I have both books onboard the Far Reach.

For me, Kittredge is the go to guy to learn celestial. He was a life long sailor. He circumnavigated in 1960 in a 38’ double ender. He taught celestial for decades. His entire thrust is “it’s not that hard.”

Karl’s book is different. He is a graduate of MIT. He is a physicist. A very smart guy. He is also a sailor. His book is not as simple as Kittredge’s book, though he does strive to make things understandable. But he clearly has a 50lb head. He explains many of the same things as Kittredge, but differently. So, while his book is not as simple to understand his explanations are just different enough that when I get stuck I can figure it out by reading what both authors have to say. In other words—the two books compliment each other by coming at the same problem from different directions. Karl’s book also offers some practical advice for incorporating celestial nav when you have zero desire to give up your GPS. And, he describes how to work the sight reductions with a scientific calculator. Remember, for Kittredge there was no other way than celestial. For Karl, it’s for fun and for back up.

But, back to Kittredge. His entire aim was to demystify celestial navigation by breaking it down into its basic parts and keeping it simple. In the opening chapter he walks you through a sun shot and sight reduction in ten steps—before there is any additional complex explanation offered. He uses a lot of humor throughout the book and on more than one occasion refers to those “brainiacs” that unnecessarily complicate it as “our Gentlemen of Confusion.”

Kittredge argues you don’t have to learn astrophysics before you learn the 10 basic steps for sight reduction. Turns out he was right. As a side note, Kittridge was a good friend of the famous double circumnavigator and sailing author Eric Hiscock. Hiscock devoted a whole chapter to Kittredge in his book “Atlantic Cruise in Wanderer III.”

How did I approach learning celestial navigation? Well, for three or four days I pretty much devoted myself to reading. Then, every afternoon I checked my watch to make sure it was set to Universal Time, via WWV on my HF receiver. Then, I rowed Sweet Pea down channel to open up a small section of the SW horizon and took a series of sun shots and recorded the time of each to the second also writing down the sextant reading. Next, I spent a number of hours in the evening working through the sight reduction process for the earlier sun shots.

I could not bring the sun down on the small section of horizon I could see from the Far Reach. So, I practiced quickly acquiring the sun in the sextant and bringing it down to the shoreline only 1/3nm away–no good for a fix but good practice all the same. There is also skill required to select the right sun shades for the horizon as well as for the sun.

I also practiced using plotting sheets and the techniques for maintaining a “running fix.” Once I felt like I had the sun LOP and running fix figured out I read through the chapter on reducing a star shot. Then, I took a star shot of Sirius in the evening at dusk. I reduced it in about 10 min. My star shot LOP was within an acceptable 2 NM…room for improvement but close enough to get me home.

Some of the tools needed for celestial navigation. You also need a sextant and an accurate watch.

This is a good time to mention that I am using HO 249 Sight Reduction for Air Navigation. HO 249 is not as accurate (.5’) as HO 229 (.1’) taught at the professional maritime trade schools but it’s simpler and faster than 229. And the small boat navigators I have read about seem pretty emphatic that 1-2 NM is about as good as you can expect on the pitching deck of a small boat off-shore. Additional advantages of 249 are it requires less books and has a better process for using multiple stars for quick-shot true fixes. It’s also the same system used by Larry Pardey, Eric Hiscock, Miles Smeeton, Hal Roth, James Baldwin and many other legendary small boat navigators. It seems to me either HO 249 or 229 is fine. But 249 is a little quicker and simpler and seems better suited to a small boat. Karl’s book describes both formats.

For either HO 249 or 229 you will need the current Nautical Almanac. I think you can get it free on line.

These are the three volumes for HO 249. They are good for five years.

Because I have only a small section of the horizon available to me I can’t practice the pre computed shots of multiple preselected stars that Kittridge claims can all be reduced in 15 minutes total (for all three shots). I can set it up and learn the steps but I can’t make the shots due to mountains all around me blocking the horizon.

This is the format I have adapted from Kittridge‘s book. There are actually two sight reductions on this page, one in the formatted blocks and another scribbled in the bottom right corner.

After reducing a bunch of shots I was running low on work sheets so I made a few by hand. I took shots and reduced them and plotted them out on the plotting sheet. I was getting pretty confident. This is not so hard I thought. Then, the next day, I could not reduce the sight. I was way off. I went back through the math and there it was, plain as day. I had transposed a critical number from the Almanac. I wrote down 105° 45’.5. But I should have written down 105° 54’.5. Thus, the calculation to get to Local Hour Angle was inaccurate, which meant the calculation derived from the tables in HO 249 were busted. I was tired…and I wasn’t even sailing.

I corrected the numbers the next morning and reworked the problems. One LOP was within 1nm the other within 2nm of my position. So, it was an error easily corrected and resulted in an accurate position. But, the lesson for me—the devil’s in the details. Be damn careful with the numbers! I’ll also refine how I actually look at the thousands of numbers in the many columns and rows of data. One tip suggested to me is to read the numbers backwards. That might be a good idea. I’ll try it out.

As previously mentioned, to avoid running out of worksheets I scribbled out my own form for the practice shots. Hand writing the data field adds to the fake drama created by the picture of the math. Seriously, there is only 6 or 7 calculations and it’s adding and subtracting only.

Hand jamming the format.

After working a few more problems I could see writing out the format by hand each time was very inefficient. I decided to make better use of the paper and wrote out the format for two sight reductions per page. Then, I took it to a local business supply store and they made double sided copies. Now I have plenty of forms for the trip home. And this particular format is good for a sun, star, or planet sight reduction.

My hand written forms for HO249 sight reduction turned into double sided copies.

I am pleased with what I have learned so far. I think I have the basics for maintaining a running fix with the Sun LOP as well as a proper fix using multiple stars. It remains to be seen what I can do in the real world of off-shore sailing but I have every intention of trying it out during the voyage home from the Virgin Islands to NC.