No. of Recommendations: 4
Correct, tilt is primary reason, elliptical orbit actually an inverse factor.
From AI search:
Earth's ~23.5° axial tilt (obliquity) is the primary cause of seasons, making sunlight more direct in one hemisphere while the other tilts away, despite the Earth's elliptical orbit around the Sun, where distance changes (closest at perihelion in January, farthest at aphelion in July) have minimal seasonal impact, with the tilt providing concentrated energy and longer days for summer and less for winter. These tilt and orbital variations, known as Milankovitch cycles, slowly change over millennia, influencing long-term ice ages, with greater tilt meaning more extreme seasons.
But a minor quibble to a thoughtful post.
