Here's why:
* Earth's Tilt: The Earth's axis is tilted at approximately 23.5 degrees. This tilt is the reason we have seasons.
* Summer Solstice: During the summer solstice in the Northern Hemisphere (around June 21st), the North Pole is tilted towards the sun at its maximum angle. This means the Southern Hemisphere is tilted away from the sun at its maximum angle.
* Southern Hemisphere Winter: Since the Southern Hemisphere is tilted away from the sun, it experiences winter during the Northern Hemisphere's summer solstice.
So, to summarize:
* During the Northern Hemisphere's summer solstice, the south end of Earth's axis is tilted away from the sun.
* During the Southern Hemisphere's summer solstice, the south end of Earth's axis is tilted towards the sun.