How to navigate using the Stars

Latest News: My new book, How to Read Water, is out soon! It includes a section that explains - in a straightforward way - how celestial navigation works.

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Lots of people love the idea of finding direction and navigating using the stars, but are put off because they fear it is complicated. It does not need to be complicated at all, it is something you can learn to do in minutes. In fact finding direction using the stars is much quicker and easier than using a compass. It is also a lot more fun.

Imagine one night you arrange to meet a friend under a lamppost on the other side of a gentle hill. As you walk towards your friend you would see the light appear over the brow of the hill, long before your friend became visible. You would know exactly what direction they were, even though you could not see them. This is the simple concept behind using the stars to find our way at night.

The stars can act as our lampposts.

All we need do is find a star that is directly above the place we need to get to and it will point exactly the right direction for us, from quarter of the globe away. If you called a friend on the telephone who was in another country a few thousand miles away, and you asked them to name the star that was directly over their head, you could then find that star in the night sky and the point on the horizon directly below that would be their exact direction from you at that moment. Unfortunately, a few minutes later that star would have moved and so you would need a new one. It would take a lot of phone calls to use this method with most stars! Fortunately there is one star in the night sky that does not appear to move. It is called Polaris, or the North Star.

The easiest method for finding the North Star is by finding the ‘Plough’, an easy to identify group of seven stars. It is known as the ‘Big Dipper’ to the Americans and the ‘saucepan’ to many others. Next you find the ‘pointer’ stars, these are the two stars that a liquid would run off if you tipped up your ‘saucepan’. The North Star will always be five times the distance between these two pointers in the direction that they point (up away from the pan). True north lies directly under this star.

Animation showing The ‘Plough’ rotating anti-clockwise about the North Star.

The ‘Plough’ rotates anti-clockwise about the North Star, so it will sometimes appear on its side or even upside down. However its relationship with the North Star never changes and it will always dependably point the way to it.

The reason the North Star is so important for natural navigation is that it sits directly over the North Pole. Something that people often forget is that whenever you are trying to find true north, you are actually trying to find the direction of the North Pole from wherever you are – even if you are only heading a few hundred metres on a gentle walk – ‘north’ is still just an abbreviation for ‘towards the North Pole’.

The constellation, Cassiopeia, is also very helpful in finding the North Star as it will always be on the opposite side of the North Star from the Plough and therefore often high in the sky, when the Plough is low or obscured.

Constellations Cassiopeia, the Plough and the North Star.

Having found the North Star, there is something about its height above the horizon that is well worth knowing. Wherever you are in the northern hemisphere, the North Star will be the same angle above the horizon as your latitude. This can be measured accurately using a sextant, but an estimate can be made using an outstretched fist. We are all different shapes and sizes, but we share proportions. An outstretched fist makes an angle of close to 10 degrees for most people. In an under a minute and with just your bare hands you can now find north and estimate your latitude.

The constellation, Orion, rises in the east and sets in the west. Orion’s belt, the only three bright stars that form a short straight line in the whole night sky rise very close to due east and set very close to due west. If you want to be really accurate then the first star in the belt to rise and set, called Mintaka, will always rise and set within one degree of true east and west wherever you are in the world.

Finding east and west using the Orion constellation to navigate.

Lots more information about these methods and lots of others can be found in my books.

They also contains lots of information on using the sun, moon, plants and animals to help you find your way, on land or at sea or even in the city.

Like this article?

For a complete guide to Natural Navigation read Tristan’s books.

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