In order not to get lost on the trip, you must have orientation skills in space, that is, easily determine your location. For a long time during sea expeditions, such a guideline was part of the land, from the coast of which the captains, fishing and transporting goods, did not go far. After all, this decision was dangerous and could jeopardize the life of the whole team.
Over time, many tools were invented to determine the location of a person in space, which allowed traveling in the open ocean. One of these is the sextant. We learn more about what a sextant is and evaluate its value in the modern 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 indicates the location of the object relative to the equator of the Earth. Longitude is counted from the prime meridian (Greenwich). He conditionally divided the Earth into the Western and Eastern hemispheres. They began to take a degree as an indicator for measuring coordinates, because the shape of the Earth is close to spherical.
In the future, navigation orientation developed rapidly. Sailors needed to know what a sextant was, to understand the principle of its work.
Mysterious device
The sextant device is a tool for finding the angle between a celestial body and a horizon line. In this case, stars or planets are used as a guide. In air devices, 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, rotated in the center of the arc. A telescope with lenses is attached to the structure and aligned with the horizon. Next, a mirror is fixed on the beam lever, which is displaced until the investigated celestial body appears half in it. When working with a sextant, the following condition must be observed: the pipe must be directed along the horizon. Next, the angle between the object and the horizontal surface is found using the arc of the sextant, on which degrees are plotted. The value of the angle and the measured time on the ship will allow you to calculate the exact coordinates of the traveler using special tables.
The meaning of the word sextant has Latin roots and in translation means "one sixth." This is due to the fact that the device in appearance looks like an arc containing only 60 degrees, or, in other words, 1/6 of a circle. The first sextant construct had a wider angle for finding coordinates.
Atmosphere Correction
An explanation of what a sextant is will be more complete when referring to the amendment table, which gives accuracy to the handy tool in question. It provides correctness and accuracy in the readings, because it allows you to take into account the effect of refraction of the atmosphere. Parallax corrections for each celestial landmark have been going on since 1762 and are 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 today's world, electronic devices like GPS are considered indispensable assistants when navigating in open water. This is especially important in cloudy weather, when neither stars, nor the moon, nor the sun are visible in the sky. Similar 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 verify data received from satellite systems.