We explain what the terrestrial axis is, where it is located and what terrestrial movements it is related to. Also, what phenomena affect it.
What is the earth's axis?
The terrestrial axis or polar axis is an imaginary line 12,713 kilometers long that joins the two geographical poles of the Earth. planet (the North Pole and the South Pole), crossing it more or less perpendicular to the equator and with an inclination of 23° with respect to the ecliptic plane, that is, with respect to the apparent path that the sun traces in the sky when it rises and hide.
This imaginary line allows us to understand the different movements that our planet makes, beyond its translation of 365 days around the Sun. In fact, the terrestrial axis represents the center of the movement of rotation of our planet (24 hours) and also the axis on which it tilts, giving rise to the phenomenon of seasons of the year, since the terrestrial axis is not completely perpendicular, like that of Jupiter, Venus or Mercury.
On the other hand, the Earth's axis is not entirely stable either. It changes orientation cyclically, in fairly long periods, which gives rise to the movements known as precession (every 25,767 years) and nutation (every 18.6 years), that is, the tilting and pitching movements that our body makes. planet. In addition, the terrestrial axis also allows defining the so-called celestial poles, which are the two imaginary points where the terrestrial axis coincides with the celestial sphere, that is, with the imaginary sphere that contains the visible universe.
Phenomena that affect the Earth's axis
It is known that the great earthquakes, stellar impacts and other cataclysmic or large-scale events can have a greater or lesser influence on the behavior of our planet, pushing the planetary axis from its 23° inclination with respect to the ecliptic to 27°, more or less.
There are also scientific studies that suggest a correlation between global warming and the displacement of the geographical poles of the planet (the so-called polar drift), given that as the temperature of the world increases, its great masses of ice melt and the distribution of weight changes, which could have incidences in the way in which the terrestrial axis behaves.