It is the one that the Earth accomplishes around the Sun. It describes an elliptical orbit of 93 million km, maintaining a speed of 29.8 km / seconds.
In this tour the Earth spends 365 days and 6 hours.
Those 6 hours which are accumulated each year, after 4 years, they are 24 (one day). Each four years there is one that has 366 days, called leap year.
The plane that determines the Earth's orbit is called the ecliptic circle and is the maximum that the Earth describes in its movement around the Sun.
The translation movement causes the four seasons.
The stations are determined by the tilt of the earth's axis on the ecliptic. According to the position of the sun-earth connection, some areas receive more solar radiation than others.
The change of seasons
Seasons are changing alternately by the hemisphere which is closer to the sun. When the northern hemisphere is the farthest from the sun, it will be winter, while simultaneously, the southern hemisphere is closer and then it is summer there.
There are 4 key positions in the movement of translation: Spring and Autumn (equinoxes) and Summer and Winter (solstices).
During the Spring equinox (March 21), in the northern hemisphere is Spring and in the Southern Hemisphere is Autumn.
During the Autumn equinox (Sept. 23), in the northern hemisphere is Autumn and in the Southern Hemisphere is Spring.
During the Winter solstice (Dec. 22) in the northern hemisphere is winter and in the south is Summer.
During the Summer solstice (June 21), in the Northern hemisphere is Summer and in the south is Winter.
Another effect of the inclination of the axis of the Earth on the ecliptic is the different duration of the day and the night, as Summer or Winter.