Does Earths orbit determine our seasons or is it Earths rotation on its axis?
Neither. It is the angle of the Earth’s pole to the ecliptic (plane of Earth’s orbit) which causes the seasons. That is why, when it’s summer in the northern hemisphere. it is winter in the southern hemisphere and vice versa. The difference in temperature between perihelion, when Earth is closest to the Sun, and aphelion, when it is farthest from the Sun, is very slight i comparison. For example, perihelion this year was on January 3, in the middle of northern winter. Northern winters are very slightly milder than southern winters at the same latitude relative to the equator, though mostly we don’t notice this because the Earth’s population at high southern latitudes is much smaller than at high northern latitudes.
