content: The Earth tilts on its axis. The North pole is tilted 23.5 degrees away the sun on December 21st (Winter Solstice), and 23.5 degrees towards the sun on June 21 (Summer Solstice). This tilting causes the path the sun appears to take across our sky to change slightly every day, rising and setting further towards the south the closer it is to the Winter Solstice (for those of us in the Norther hemisphere).