Published July 30th, 2018

One interesting aspect of living in Paris that I’ve mentioned a few times is how late the sun stays out. Part of this is a result of the time zone Paris is in, but part of it is also because of how far north it is.

Before coming to France, I knew it was further north than New York City. When I was growing up, I kinda had this image of Europe being like a mirror to the east coast of America:
-up north in Sweden and Norway it was like living in Canada,
-London/Paris were like Boston/New York City,
-and the southern part of Spain was like living in Florida,
and based on the températures/climates in those régions, that’s almost right.

But if you look at the actual coordinates, Paris is actually further north than the most northern part of Maine! The lattitude for the northern most point in Africa is just north of Norfolk, Virginia. Because of the Earth’s axis of rotation, the further north you are, the more daylight there is per day (in the “summer” months) – in fact, if you go far enough north, the sun doesn’t set in the summer time.

What dawned on me today is the opposite is also true – in the winter, the days in Paris will be shorter than in (most of) the US. Here’s a little chart I put together comparing the amounts of daylight in various locations. For a little puzzle, try to figure out which day of the year Paris will get the same amount of daylight as Farmingdale.

		Paris	Santa Fe	Farmingdale	Troy
Longest Day	Start of Daylight	05:46	05:48	05:22	05:16
	End of Daylight	09:57	08:22	08:28	08:36
	Hours of Daylight	16:11	14:34	15:06	15:20
Shortest Day	Start of Daylight	08:41	07:09	07:14	07:21
	End of Daylight	04:56	04:54	04:29	04:23
	Hours of Daylight	08:15	09:45	09:15	09:02

I guess we’ll have to enjoy the longer days while they last!

Have you figured out the puzzle?

There are actually two days a year where every location on the planet gets the same amount of daylight, and those two days are the Spring Equinox and Autumn Equinox – on these days, the Equator is almost perfectly in line with the sun, so everywhere gets about 12 hours of daytime. One more note – the word for “Equinox” comes from the Latin “aequinoctium”, made up of aequus (equal) and nox (night), because there is an equal amount of night time everywhere.