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Which Night is the Longest Associated with Winter Solstice?

-- Pearl | December 22, 2021

Question:

Which is the longest night of winter solstace? The night that follows the day of the solstice or the night that comes before?

-- Pearl

Answer:

In fact, Winter Solstice, which occurs in the northern/southern hemisphere when the Sun’s path is at its furthest south/north point in its path through the sky, occurs at a specific time. The longest night, then, will be the night closest to the actual solstice for your location. In 2021 the Winter Solstice occurs on December 21 at 15:59 UTC, which is 10:59 a.m. EST in the United States. Since this time is closest to the night of December 20/21, or the previous night, on the East Coast of the United States, the night of December 20/21 will be the longest night in 2021 on the East Cost of the United States. If you are located in Europe, though, the Winter Solstice occurs closest to the night of December 21/22, making that night the longest. Note, though, that the difference in the total length of the night on December 20/21 compared to December 21/22 is less than a minute, so both nights will appear to be the same length to most people.

-- Jeff Mangum

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