The rays of the sun strike the Earth at the northernmost and southernmost positions during the solstices.

Here's why:

* Summer Solstice: The sun's rays hit the Earth at the most northern point possible. This is the longest day of the year in the Northern Hemisphere and the shortest day in the Southern Hemisphere.

* Winter Solstice: The sun's rays hit the Earth at the most southern point possible. This is the shortest day of the year in the Northern Hemisphere and the longest day in the Southern Hemisphere.

The exact dates of the solstices vary slightly each year, but they typically fall around June 21st (Summer Solstice) and December 21st (Winter Solstice).