Astronomical factors 4

This obliquity and the fact that the Earth describes an elliptic (and not circular) orbit have an influence on the interception of Sun's radiation by the Earth, a fact which explains that seasons do exist.

Earths orbit around the Sun is slightly elliptical. Aphelion is currently reached on July 5, and Perihelion on January.


*Astronomical factors 4*
	3 - Variation in the excentricity
	This obliquity and the fact that the Earth describes an elliptic (and not circular) orbit have an influence on the interception of Sun's radiation by the Earth, a fact which explains that seasons do exist. Earths orbit around the Sun is slightly elliptical. Aphelion is currently reached on July 5, and Perihelion on January.