In the infinite space of the universe at a speed of 250 kilometers per second, the Sun and the surrounding planets move. In turn, within this system, all the components of its celestial bodies move around the central star, along different trajectories (orbits) and at different speeds.
Most of these planets have their own planet-satellites, called satellites. The presence of satellites, the constant movement of them around their planets and the existence of certain regularities in the ratio of the sizes of these celestial bodies and the distances between them explains the causes of solar eclipses.
Each of the celestial bodies entering our system is illuminated by the sun’s rays and every second casts a long shadow into the surrounding space. The same shadow of a cone-like shape throws the Moon onto the surface of our planet, when it moves in its orbit between the Earth and the Sun. In a place where the lunar shadow falls, an eclipse occurs.
Under normal conditions, the apparent diameters of the Sun and the Moon are practically the same. At a distance of 400 times less than the distance from the Earth to the single star of our system, the Moon is 400 times smaller in size than the Sun. Thanks to this surprisingly accurate ratio, mankind has the opportunity to periodically observe a total solar eclipse.
This event can occur only in periods when several conditions are met at the same time:
1. New Moon – The moon is facing the Sun.
2. The moon is on the line of nodes: the so-called imaginary line of intersection of the lunar and terrestrial orbits.
3. The moon is at a distance close enough to Earth.
4. The line of nodes is directed toward the Sun.
During one calendar year there may be two such periods, i.e. minimum 2 eclipses in 365 days. Moreover, during each period of such phenomena there may be several, but not more than 5 per year, in different parts of the globe.