Winter solstice is an astronomical phenomenon which marks the shortest day and the longest night of the year. Winter solstice occurs for the Northern Hemisphere in December and for the Southern Hemisphere in June.

The axial tilt of Earth and gyroscopic effects of its daily rotation mean that the two opposite points in the sky to which the Earth’s axis of rotation points change very slowly (making a complete circle approximately every 26,000 years). As the Earth follows its orbit around the Sun, the polar hemisphere that faced away from the Sun, experiencing winter, will, in half a year, face towards the Sun and experience summer. This is because the two hemispheres face opposite directions along Earth’s axis, and so as one polar hemisphere experiences winter, the other experiences summer. Continue reading →