section_path: Causes and effects/Axial parallelism
section_name: Axial parallelism
paragraph_text: Axial parallelism
  
  The Earth's orbit exhibits approximate axial parallelism, maintaining its direction toward Polaris (the "North Star") year-round. This is one of the primary reasons for the Earth's seasons, as illustrated by the diagram to the right. Minor variation in the direction of the axis, known as axial precession, takes place over the course of 26,000 years, and therefore is not noticeable to modern human civilization.