In order not to get lost on a journey, you must have the skills of orientation in space, that is, to easily determine your location. For a long time, during sea expeditions, such a landmark was a part of the land, from the coast of which captains, fishing and transporting goods, did not go far. After all, this decision was dangerous and could endanger the life of the entire team.
Over time, many tools were invented to determine the location of a person in space, which made it possible to travel in the open ocean. One of these is the sextant. Let's learn more about what a sextant is and appreciate its importance in today's digital world.
Find the unknown
For a long time, sailors were afraid to go out into the open water. This task has been greatly simplified with the introduction of the concept of geographical coordinates. Latitude refers to the location of an object relative to the Earth's equator. Longitude is measured from the prime meridian (Greenwich Mean Time). He conditionally divided the Earth into Western and Eastern hemispheres. For the measure of steel coordinatestake a degree because the shape of the Earth is close to spherical.
In the future, nautical orienteering developed rapidly. The sailors needed to know what a sextant is, to understand how it works.
Mysterious Device
The sextant is a tool for finding the angle between a celestial body and the horizon line. In this case, stars or planets are used as a guide. In aircraft, such a device is used to determine longitude and latitude.
After finding out what a sextant is, it is necessary to describe in more detail the appearance and principle of its operation. Structurally, it is a metal arc with equal divisions of degrees with a moving beam lever turned in the center of the arc. A spyglass with lenses is attached to the structure and aligned with the horizon. Next, a mirror is fixed on the beam lever, which is shifted until the investigated celestial body appears halfway in it. When working with a sextant, the following condition must be observed: the pipe must be directed along the horizon line. Further, the angle between the object and the horizontal surface is found using the arc of the sextant, on which the divisions of degrees are plotted. The value of the angle and the counted time on the ship will allow using special tables to calculate the exact coordinates of the traveler.
The meaning of the word sextant has Latin roots and means "one-sixth". This is due to the fact that the device in appearance seems to be an arc containing only 60 degrees,or, in other words, 1/6 of a circle. The first construct of the sextant had a wider angle for finding coordinates.
Atmospheric Correction
An explanation of what a sextant is will be more complete when mentioning the correction table, which gives accuracy to the tool in question. It provides correctness and accuracy in the readings, because it allows you to take into account the effect of atmospheric refraction. Parallax corrections for each celestial landmark have been maintained since 1762 and updated annually. Updated data are regularly published in specialized publications.
Modern navigation
Now many have heard about GPS, GLONAS and other navigation and satellite systems. In the modern world, electronic devices like GPS are considered indispensable aids in navigating open water. This is especially important in cloudy weather, when neither stars, nor the Moon, nor the Sun are visible in the sky. Such modern devices lead to the fact that the popularity of the sextant is gradually disappearing. However, we note that there are cases when ship captains use it to check data received from satellite systems.
