For thousands of years people somehow found their way without GPS. For most of history a compass wasn’t used either. Yet the world was explored and new lands were discovered. Even more astounding, these intrepid pioneers found their way home again. How did they do it? By using ancient wisdom. They learned how to navigate by the stars.
With over 6000 stars visible from earth on a clear night, navigation by stars can seem intimidating. But not if you take into account that only fifty-eight are useful for navigation, and you only have to know thirty-eight constellations to find your way.
To make it really easy, the majority of celestial navigation relies on only four constellations. That’s it. Four groups of stars can make the difference between being hopelessly lost in the woods and spending the night comfortably in your tent.
Polaris is the Key
In the Northern Hemisphere one star stands above all others when it comes to understanding where you are and where you’re going. Polaris, or the North Star, is the most reliable light in the sky and if you only know how to locate one star, Polaris is the best choice.
Why is it so reliable? Polaris sits almost exactly above the Earth’s rotational axis. Like the handle on a top, Polaris stays more or less in one place while our planet spins below. It does move in a very small circle, but it does not rise and set like everything else in the sky. So, once you locate Polaris, you know where north is and the other points of the compass are easy to determine from there.
Locating the North Star is the best celestial navigation strategy you can have. Fortunately, there are several ways to find Polaris. Here are the best three to use when plotting a course in the dark.
Finding Polaris Using the Big Dipper
The easiest way to find Polaris is by using the constellation known as the Big Dipper, or Ursa Major. The Big Dipper is one of the most easily recognized constellations in the sky and its bright stars are easy to see, even in less than optimal conditions.
The Big Dipper looks like a deep frying pan, or a ladle, with a long handle. At the end of the ladle, opposite the handle, are two pointer stars. These two stars, Merak and Dubhe, point directly at Polaris. By tracing an imaginary line through both, and extending that line five times the distance between the two pointer stars, you will arrive at Polaris.
Remember, the constellation and the pointer stars rotate counter-clockwise around Polaris, which doesn’t move. This means at times your imaginary line will be traveling downward or across the sky. It won’t matter. As long as you create your line using the two pointer stars you will find Polaris.
Finding Polaris Using Cassiopeia
At certain times of the year, the Big Dipper will be too low in the sky for you to see. Don’t panic. You have a backup plan. Polaris can easily be found using Cassiopeia as well.
Cassiopeia is a bright constellation shaped like the letter “W”. This shape is made of two “Vs”. One is wider than the other. Find the wider “V’ and make a line that bisects it. This line will lead you directly to Polaris.
Even if the Big Dipper is visible, most celestial navigators use Cassiopeia to double check they have the right location for Polaris. When it comes to getting a bearing in the wilderness, it’s better to be safe than sorry.
Finding Polaris Using the Little Dipper
Using the Little Dipper, or Ursa Minor, to find the North Star is by far the easiest method. Unfortunately, the stars that comprise this constellation are not very bright and often are hard to see under normal conditions.
If you are fortunate and can see the Little Dipper you will notice one bright star at the end of the handle. That is Polaris. To double check, you can locate the Big Dipper and Cassiopeia and work your way backwards to verify you have the correct star.
Using Polaris to Determine Latitude
The North Star can also be used to discover your latitude. Once you have located Polaris, latitude can be determined by measuring its distance over the horizon. This is best done using a sextant but if you forgot to pack one your fist will do in a pinch.
A human’s fist when held at arm’s length will be approximately ten degrees of latitude. By measuring this way from Polaris to the horizon you will know your latitude. For example, if you are near Boise, Idaho you can expect Polaris to be a little more than four fists high as that city has a latitude of forty-three degrees.
While this method may not be precise enough to draw a map, it is an excellent way to verify that the star you are following is Polaris.
Finding East, West, and South Using Orion
At certain times of the year you will find one constellation dominating the sky. It is easy to find and use as a navigational aid. It is called Orion, or the Hunter. Orion is unique because it contains three stars in a nearly straight line. This makes for easy recognition by even the most novice stargazers. Once the line, or belt, is located the rest of the hour glass shape is simple to recognize.
Orion rises in the east and sets in the west. The right-most star in its belt, named Mintaka, is the one to watch. It’s path across the sky is within one degree of true west. On the clearest nights, a special feature of Orion is visible. Descending from the middle of the belt are three stars. This is Orion’s sword. It points almost due south.
Navigating by Moonlight
The moon is another valuable tool to use when navigating, if the conditions are right. Often, a crescent moon is the simplest way to find your heading when it is too cloudy and overcast for the stars to be of much use.
If you see a crescent moon draw a line from tip to tip down to the horizon. This is south. If the moon rose before the sun set, the round side will face to the west. If the moon rose after midnight the round side will face to the east.
Determining Direction Using Any Visible Star
Stars constantly move across the sky. This is a bad thing if you are trying to use one as a bearing but it is great if you are lost. The two-stake method is a quick way to establish direction without having to memorize constellations and will work as long as you can see a single star.
The Two Stake Method
- Take two stakes and pound them into the ground about three feet apart.
- Line up one star with the top of both stakes.
- Observe the movement of the star for twenty minutes.
- If the star moves left, you are facing north
- If the star moves right, you are facing south
- If the star rose, you are facing east
- If the star dropped, you are facing west.
This technique will work with any star except Polaris. It is not a precise direction finder but it will quickly orient you when lost.
Finding South in the Southern Hemisphere
Celestial navigation is very different in the Southern Hemisphere because Polaris cannot be seen. Luckily, there is a substitute that marks the southern axis. It is a constellation called Cruxe, or the Southern Cross.
Cruxe is said to look like a kite and is comprised of four stars which form two lines, like the ribs of a kite, or a cross. The longer of the two lines will point south. Like Polaris, Cruxe stays fixed over the South Pole and is the most reliable point of navigation in the Southern Hemisphere.
How to Use What You Have Learned from the Stars
Once you have established one point of the compass it is easy to fill in the other three. If you’re planning on moving at night, establish your direction of travel relative to the point of the compass you discovered and create a reference point to help you move in a straight line.
For instance, if you want to travel south and have found Polaris, keeping the North Star at your back will keep you heading on the right course. Westward travel will find Polaris on your right shoulder.
Another way to reference your bearing is to establish a route based on the hour hand of a clock. Traveling east would mean keeping Polaris at your nine o’clock, for example. Your desired course will always be twelve o’clock.
Saving Your Bearings for Daylight
A good plan in rugged terrain is to establish your direction at night and travel during the day when you can see obstacles and hazards. To do this, you must preserve the bearings you created with your knowledge of the stars.
When you have discovered a direction through celestial navigation, draw or mark the points of the compass you establish with rocks or branches. Make sure to define all four points and confirm your accuracy with as many techniques as you remember.
In the morning use these markers to set a heading by choosing your course and picking a geographic feature to aim for. Mountains and especially tall trees work great for this purpose. If you cannot find something suitable in the distance, or have limited vision due to heavy vegetation or hilly terrain, choose waypoints on your heading at closer intervals.
Each time you reach a waypoint set a new one on the same heading. Don’t forget to look backwards for a reference point. Having a reference behind you and in front gives you the ability to stay on a straight line.
At the end of each day, mark your heading with rocks or branches and verify your heading when the stars come out. Make any necessary corrections at this time for the next day’s journey.
Telling Time by the Stars
The stars hold a lot of information if you know how to find it. It is even possible to tell the time by simply looking at the North Star. Remember that line you drew from the Big Dipper’s pointer stars to Polaris? Picture that line as the hour hand on a twenty-four hour clock. Also, this clock runs counter-clockwise.
The Big Dipper constantly rotates so your hour hand needs to be adjusted according to the time of year. On March 06, this celestial clock is right on time. For every month after this date multiply by two and subtract from the time your Polaris clock is showing. It’s not perfectly accurate but it should be in the ballpark.
Cassiopeia can be used the same way. Reference the line you created by bisecting the wider V and use March 21 as your zero date.
Using the stars to find your way does not have to be difficult. As you can see, it only requires knowledge of four constellations and some easy steps to decipher what you find in the sky. Without proper tools, you cannot expect to be perfectly accurate but you should be able to set a course close to the direction you wish to travel or at least understand in which direction you are looking.
Like making fire or building a shelter, celestial navigation can be a critical survival tool when the chips are down. It is easy to learn and easy to teach to others. And, it can be fun. Who doesn’t want to spend an evening in the wilderness staring at the stars and mastering a bushcraft skill?
Just remember, there is no substitute for preparation. Even if you have considerable experience using constellations to find your way, there is no substitute for a good compass and a quality map. No one says you have to use them but they are nice to have if you run into a foggy night and are not quite sure which direction is home.
Do you navigate by the stars? Do you have any stories to share about finding your way without a compass, GPS, or a map? If you do we’d love to hear from you in the comments section.