The Sun And The Moon In The Ancient World

In this case, knowing from the astronomical calculations of the position of the sun at any time, you can simply, with the help of these measurements of the height of the sun, determine the position of the zenith point for any time; For this it is necessary only to have an instrument by means of which it is possible to measure and take into account the movement of the zenith point irrespective of the rotation of the earth around its axis, that is, to eliminate the effect of the apparent rotation of the celestial vault. The Sun And The Moon In The Ancient World ...

It is known that the position of celestial bodies, as well as the zenith for different places of the globe, is determined in the celestial sphere in exactly the same way as the position of various points of the earth is determined, namely, along equatorial longitude and; Latitude. The first meridian, from which the longitudes (along the equator) are considered, is the one that passes through the world's pole and the point of the vernal equinox. Even in ancient times people knew that the moon is in the signs of the zodiac, and in each sign it is a certain time, after that it goes to the next sign of the zodiac, the Moon in Aries, the Moon in Cancer ....

The equatorial latitude of any point in the sky is the smallest arc distance from the celestial equator, while the geographic latitude of some point on the earth's surface is the angle formed by the vertical direction of the given terrain with a plane parallel to the equatorial plane.

Consequently, having the calculations of the solar motion, you can at any time determine the equatorial longitude and latitude of the sun; From here, producing the above two measurements of the height of the sun with a chronometer showing a completely uniform change in the equatorial longitude of the zenith at the place of observation, one can determine the equatorial longitude and the zenith latitude for any moment.

But on the basis of the foregoing, the equatorial latitude of the zenith at the place of observation is none other than the geographical latitude of this point. Equatorial zenith longitude is not yet a quantity for determining the location of the earth's surface, since it is not considered from any particular meridian on earth, but from the above-mentioned first meridian of the celestial sphere; With respect to this meridian, the zenith continuously changes its position due to the rotation of the earth.

The Sun And The Moon In The Ancient World