03 Feb What is Sextant?
While taking your physics tuition, have you ever wondered at what position on earth you are in? Today in physics tuition, we will know about sextant. The sextant is a device or instrument that has been used for centuries to measure angles, principally altitudes of celestial bodies like the stars or the sun. It is further used to navigate planes and ships for latitude determination in earlier days.
The word sextant came from the Latin word, “Sextus” that means ‘one sixth’. Apparently, the sextant is fitted with an arc that is usually of 60° or ‘one sixth’ of a circle. The shape of a sextant resembles the wedge of a pie and throughout the round edge, there are marks of a scale.
John Hadley, an Englishman invented sextant in 1731. The main purpose of sextant was to determine the latitude of a ship or its distance from the equator. The foundation of the modern navigation technology was laid through the invention of the sextant.
The instrument has an arc of a circle that has consistent marks in degrees along with a radial movable arm pivoted at the circle’s centre. At the arm’s end, there was fixed a movable mirror. The other end extends to the scale. On the sextant, there is a telescope mounted as well as a glass mirror in front of it.
The sextant is operated by the operator by looking straight at the horizon through the telescope and then moving the mirror to make any particular star or the sun to appear precisely on the horizon. The measurement of the angle required is given by the movement of the mirror on the arc. Once you know the angle, you can calculate the latitude of that place and the exact time of the day through matching with the published data table. In the middle of the vast ocean or any deserted area, this information is extremely vital to understand the exact location of the operator.
We hope you are finding your physics tuition extremely interesting. Will come back again with more such interesting stories and findings for your next physics tuition.