Posted in Web Winter solstice 2019 explained: When and why it happens December 30, 2019 The winter solstice (December in the north, June in the south) arrives at the time when that tilt is at its most extreme angle. This astronomical event appears on calendars as the first day of… https://www.nationalgeographic.com/news/2017/12/winter-solstice-2017-first-day-winter-definition-space-science/