All approximate methods for determining azimuth are mainly based on determining the north-south direction on the ground, according to local signs. What are these signs by which you can determine the north-south direction? First of all, you should turn to the heavenly bodies. They are the most reliable guides. Their use has been known since ancient times..
Locating north-south directions without a compass, by sun, sun and clock, moon, moon and clock, and stars.
The mention of the “guiding star” is found in ancient literature. This suggests that even in ancient times, when there was no compass, people knew how to navigate the sun, moon and stars. And now it’s not always possible to trust the compass. In places where there are deposits of iron ore deep in the earth, the magnetic needle may deviate so far from the true north-south direction that it will be impossible to use the compass.
And observing the position of the heavenly bodies, we can relatively accurately determine the north-south direction, and therefore the azimuth to the selected object. How do you determine the sides of the horizon by the sun?
Locating North-South by Sun.
At first, people determined the sides of the horizon by sunrise. Moreover, the word east itself is a modified word “sunrise”. In Latin, “east” – “orient”, apparently, from this came the word “orient”. Even the primitive peoples enjoyed special attention and worship..
From the east, the sun appeared – a source of light and heat on Earth. They prayed to the east, which is why the altars of the churches are facing east. When orienting on the terrain, this must be taken into account, since many more of these ancient monuments have been preserved on the earth.
Over time, people noticed that navigating by sunrise is not entirely correct, since these data are only true twice a year: on the days of the spring and autumn equinox (March 21 and September 23). On these days, day is equal to night; on the whole globe, the sun just rises in the east. The rest of the year, the places of sunrise and sunset are not exactly in the east and west..
Therefore, only at noon, from the shadow of vertical objects, it is possible to determine the exact north-south direction, and from it already the east-west direction. For our geographical latitudes at 7 o’clock in the morning the sun is in the east, at 1 o’clock in the south and at 19 o’clock in the west.
Locating North-South Directions by Sun and Clock.
But how to find the sides of the horizon by the sun in general at any time of the day? To do this, there is a way to determine the sides of the horizon by the sun and hours. The watch is placed on the palm of your hand so that the hour hand is facing the sun.
The angle that is formed on the watch dial between the clockwise and the number 1 is divided in half. The line that separates this angle will be the north-south direction. At the same time, the south is on the side where the sun was in the middle of the day.
Locating north-south on the moon.
The position of the moon in the sky is very precisely defined at every given moment and relative to the sun. This means that even half the moon you can also accurately determine the sides of the horizon. On a moonlit night, during the full moon, the moon is at 19 o’clock in the east, at 1 o’clock in the south and at 7 o’clock in the west.
During the first quarter (the fourth part of the surface of the moon) it is in the south at 7 p.m. and in the west at 1 p.m. With this in mind, it is already possible to determine the north-south direction from the moon, and from it the azimuth to any local object. During the last quarter, the moon is at 1 a.m. in the east, and at 7 a.m. in the south.
And how to distinguish the first quarter from the last? It turns out that it is very simple. At the moon of the first quarter, the “horns” are directed to the left side and the finger attached to them shows the letter “P” and the word “grows”. In the last quarter, the “horns” are directed to the right and form the letter “C” and the word “is aging”. So you can distinguish the first quarter of the moon from the last.
Locating North-South by Moon and Clock.
In this method, it is required to divide by eye the radius of the disk of the moon into 6 equal parts and estimate how many such parts are contained in the diameter of the visible crescent of the moon. If the moon arrives (“grows”), then the resulting number must be subtracted from the hour of observation. And, on the contrary, in case of damage to the moon (“aging”), the indicated number must be added to the hour of observation.
The received amount or difference will indicate the hour when the sun will be in the direction where the moon is observed (in the afternoon). Therefore, having determined this hour and taking the moon for the sun, you can easily determine the north-south direction by the clock and moon, as described above. Remembering, of course, that it is not the hour hand that should be directed to the moon, but the division of the clock face, which was calculated by the above method.
The position and size of the moon we observe at 5 hours 34 minutes in the morning. The visible part of the moon’s disk in diameter contains ten sixths of its radius per eye. The moon is “aging”, therefore, it is necessary to add to the hour of observation its size: 5 hours 34 minutes +10 hours = 15 hours 34 minutes. Set this number on the clock face of the moon, then a straight line bisecting the angle between the specified number and the number 1 on the dial will show us the north-south direction.
In the full moon, when the entire disk of the moon is visible, that is, when the moon and the sun are in the same direction, you should direct the hour hand directly at the moon and determine the north-south direction as if it were the sun.
Locating North-South Stars.
But what to do when the moon is not visible? We must be able to navigate the stars. Looking around the night sky with many lights on it, we can always find seven bright stars that form, as it were, a huge bucket, called the constellation Ursa Major. The clear location in the sky, high brightness, high standing above the horizon, good visibility in winter and summer, made them the most noticeable in the sky of the Northern Hemisphere.
And so, thousands of years ago, on these stars, as on a compass, the Phoenicians and Greeks drove their ships across the seas and oceans. And in our time, the brightly flickering lights of Ursa Major are guiding lights during night voyages, flights, land movements at night.
If you connect the two extreme stars of the Ursa Major bucket and mentally continue this line for five of the same distances, it will reach the North Star, which always points north. She is the last star in the “tail” of the constellation Ursa Minor. It also consists of seven stars, but less bright, and also has the shape of a bucket, but much smaller. The accuracy of determining the true meridian direction by this method is 1-2 degrees.
Definition of the parties of the horizon according to various local signs.
The determination of the sides of the horizon by various local features is less reliable than by celestial bodies. Therefore, you must use them carefully, checking the results in different ways. There are a lot of these orienteering methods. They can be subdivided depending on the varieties of terrain: for forest, steppe, mountains, settlements, deserts. In addition, there are ways to navigate in the winter, following the traces of the wind, along living landmarks and others.
Based on the book “Map and Compass My Friends”.