Winter solstice 2021 brings the year’s longest night to Northern Hemisphere

The winter solstice of 2021 occurs today (Dec. 21), marking the official beginning of winter in the Northern Hemisphere and it brings good news:  From tomorrow on, days will start getting longer again, taking us out of the darkness as we slowly head towards spring. 

The winter solstice marks the moment in Earth‘s orbit around the sun when the planet’s South Pole is the most tilted towards the star. That means the Southern Hemisphere is receiving a lot of sunshine (and the start of its summer season) while the Northern Hemisphere is receiving much less. This effect is caused by the inclination of the axis around which Earth rotates with respect towards the plane of its orbit around the sun. On Earth, the effect can be observed as a regular shift of the path that the sun travels from East to West between sunrise and sunset.