When Is The Shortest Day In 2024. For the more than 6 billion people living in the northern hemisphere, this astronomical event signals not only the shortest day but also the longest night of the year. The winter solstice is a celestial milestone, marking the shortest day and longest night of the year.

For those in the northern hemisphere, saturday, december 21, will mark the shortest day and longest night of the year. The astronomical winter season will continue until.