Celestial Navigation

The Big Dipper

The Big Dipper Can Point the Way

For at least a thousand years, humans have made their way from here to there using some form of celestial navigation.

The ancient Polynesian navigators regularly made their way some 2,600 miles from Tahiti to Hawaii and back with no compass, no sextant, no chronometer, no nothing...except their knowledge, which included an in-depth understanding of the workings of the sun, the moon, and the stars.

If the Polynesians can cross vast oceans without instruments, you can certainly learn to cross several kilometers of terrain without a compass or a GPS.

To help you in that endeavor, be sure to visit the hyperlinked pages below:

I. Navigate by the Sun

To be able to navigate by the sun, you must first know how the sun works. You don't have to be a Ph.D. astronomer to do so. You just need to know a few simple facts, which I've laid out in four pages in the following section. Study these pages, and you'll be well on your way to finding direction by the sun to within about 10 degrees. That's a pretty cool thing to be able to do. Having this ability, means you won't be totally dependent on a compass to find your way.

Rather watch video instead of read? Check out my Youtube video playlist on finding direction by the sun. It's all explained in my video playlist for you. Just click on the hyperlink below:


https://www.youtube.com/watch?v=gUzzHxmDIDw&list=PLAKQQ_U2cpR0BU8Oz5517kwemciOfJX7f


A. How the Sun Works 

1.  How the Date Affects the Direction of Sunrise and Sunset 

2.  How Latitude Affects the Direction of Sunrise and Sunset

3.  How the Sun's Amplitude Changes

4. The Sun's Symmetrical Path Across the Sky

Once you understand how the sun works, you can then use the sun for direction finding. With a bit of practice, you can usually be accurate to within 10 degrees or so, and that level of accuracy is plenty good enough for most pathfinding objectives, especially considering you'll be making good use of baselines (i.e. linear features) to find your way.

B.  Direction Finding by the Sun


II. Star Navigation 

A. Northern Hemisphere 

1. Polaris -- Located in the north at an altitude equal to our latitude, this is the night sky's best direction finder.

2. The Big Dipper -- This prominent star grouping points the way to Polaris.

3. Cassiopeia -- On the other side of Polaris from the Dipper, this "M" or "W" shaped pattern also helps us find Polaris.

4. The Charioteer -- Once again helps in finding Polaris.

5. Pegasus -- Its stars point to Polaris.

6. The Northern Cross -- Another Polaris pointer

7. The Orion Constellation -- The lead star in Orion's belt always rises due east and sets due west, no matter where you are on earth.

8. Scorpius -- Points the way south.

B. Southern Hemisphere 

The Southern Cross

III. Navigate by the Moon

At night, as long as the stars are visible, you don't need the moon to find directions. But on cloudy nights, the moon may be the only visible direction finder. So, to find your way at night without a compass, it's important to know how to find directions by the moon. Since how you find directions by the moon depends on the moon's current phase, let's review the moon's phases throughout the lunar cycle.

A. How the Moon Works 

B. Finding Directions by the Moon

1.  Directions by the Waxing Moon

2.  Directions by the Full Moon

3.  Directions by a Near Full Moon

4.  Directions by the Waning Moon

Finding Direction vs. Finding Position

When I say "celestial navigation," for our purposes I'm talking primarily about finding direction by heavenly bodies, that is finding which way to go. You can do this easily without instruments at all.

You may ask yourself, "Why not just use a compass?"

Good question. Here's the answer: A good navigator never likes to rely on any one bit of information, but always seeks some corroboration of whatever information is at hand. The more navigational information you have, the better.

A compass provides you with direction, but compasses can occasionally be misleading, such as when it's held too close to some metal object which throws the needle off. It's reassuring to be able to glance at the sky to confirm what your compass is telling you.

And of course, the day may come when you find yourself having to navigate without a compass.

A friend of mine, for example--I won't say who, Don--once accidentally stepped on and broke his compass while trying to find his way out of the woods on a dark night. With some combination, I suppose, of Divine Providence, good-old-boy intuition, and just plain old dumb luck, he and his buddies did manage to stumble upon a road and make it back home.

At times like those, it would be most helpful to be able to tell direction from the stars or the moon, provided of course, they're visible.

You can certainly use the sun, the stars, or the moon to find your position, but to do that with any degree of accuracy you'll need some precision tool such as a sextant.

If you're careful, you can use a sextant to fix your position to within a mile or two or three. Such precision is useful if you're 1,700 miles out in the Pacific, but it won't help you find your way the mile or so back to your truck.

That's not to say, however, that a sextant has no place in land navigation. The late Bradford Angier, a north woodsman who was also a prolific writer, explained in his book The Wilderness Route Finder how he used a sextant and some rudimentary knowledge of celestial navigation to help make his way across the vast Canadian wilderness.


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