The system of geographical coordinates is necessary in order to accurately determine the location of the object on the surface of the Earth. As is known, this system consists of geographical latitude and longitude. The first element of this system is the angle between the local zenith (noon) and the equatorial plane, which ranges from 0 to 90 degrees to the west or east of the equatorial border. Longitude – it is the angle formed by two planes: the meridian passing through a given point of the terrain and the greenwich meridian, i.e. zero point. From the latter, the longitude begins, which ranges from 0 to 180 degrees east and west (east and west longitude). Knowing how to navigate the terrain using the definition of latitude and longitude will help you communicate your exact coordinates when an emergency situation arises, when you find yourself in an unfamiliar place that is not marked on the map, or get lost in the forest. You can find out how to determine the latitude and longitude of your location.
How to determine the place by latitude and longitude How to determine the place by latitude and longitude
Determination of local geographical longitude is carried out using ordinary hours. To do this, you need to install on them the exact time of the location of the current location. Then it is necessary to determine the time of the local noon, a time-proven method will help in this: you must find a meter or half meter stick and stick it vertically into the ground. The length of the drop shadow line will indicate the time intervals to be detected. The moment when the shadow is the shortest is the local zenith, i.e. gnomon shows exactly 12 o’clock in the afternoon, with the direction of the shadow – from south to north.
At this time, you need to detect the time on the clock. – this will be the average Greenwich time reading. From this value you need to subtract the indicator, which is taken from the table of the equation of time. This amendment arises due to the inconstancy of the angular velocity of movement and the dependence on the season. Given this amendment, the average value of the Greenwich time is reduced to true solar time. The resulting difference between this solar time (ie, 12 hours) and Greenwich, as amended, must be converted to a degree value. To do this, you need to know that in one hour the Earth rotates by 15 degrees (if you divide 360 degrees by 24 hours) of longitude, or by 1 degree in four minutes. If it is noon in this area before Greenwich, in your calculations indicate the east longitude, if later, then the west. The closer the coordinates of the desired area to the polar regions, the more accurate the longitude measurements will be.
After finding the value of longitude, you can begin to determine the value of the latitude of a particular area. First you need to determine the duration of the daytime, which begins at sunrise and ends with the setting of the sun. Next you need to make a nomogram, i.e. definition of latitude: in the left part indicates the value of the length of daylight, in the right – date. If you combine these values, you can determine the place of intersection of geographic latitude with the middle part. The location found will indicate the local latitude. When determining the latitude relative to the southern hemisphere, it is necessary to add 6 months to the required date. The second way is to find the latitude with the help of a conventional protractor: for this, a plumb (a thread with a weight) is fixed in the center of this instrument, and its base is directed at the Polar Star. The angle formed by the plumb line and the base of the protractor should be reduced by 90 degrees, i.e. subtract this value from its value. The value of this angle indicates the height of the Polar Star, i.e. the height of the pole above the horizon. Since the geographical latitude is equal to the magnitude of the pole above the horizon of a particular location, this value will indicate its degree.