When the Summer Solstice is in the Northern Hemisphere and the Winter Solstice is in the Southern Hemisphere the sun is lined up with the Tropic of Cancer. When the Summer Solstice is in the Southern Hemisphere the Winter Solstice is in the Northern Hemisphere and the sun is lined with the Tropic of Capricorn .

When the Vernal Equinox is in the Northern Hemisphere and the Autumnal Equinox is in the Southern Hemisphere the sun is lined up with the equator and each Hemisphere gets the same amount of day and night. This means there are 12 daylight hours and 12 night hours. When The Autumnal Equinox is in the Northern Hemisphere and the Vernal Equinox is in the Southern Hemisphere the sun is lined up with the equator. That means that each Hemisphere gets the same amount of daylight and darkness.