Earth's orbit is very nearly -- but not quite -- round, so the difference between perihelion (its closest point to the Sun) and aphelion (its furthest point from the Sun) is small compared to the size of the orbit.

Here's a view of the Earth's tilt on the summer solstice. Summer is when your hemisphere is tilted towards the Sun and receives sunlight more directly. You can see that while it's summer in the northern hemisphere, it's winter in the southern -- and if you're at the south pole, your view of the Sun is blocked completely by your horizons!

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