The shortest day of the year in Toronto is December 21, which is the winter solstice in the Northern Hemisphere. If you're not an early riser, however, it won't necessarily feel like it. That's because Toronto is currently experiencing the earliest sunsets of the year — a phenomenon that contributes to the pending sense of doom brought forth by winter's arrival.
Between December 2 and 15, sunset in Toronto falls at 4:41 p.m. During this same period, sunrise consitently takes place later, ranging from 7:33 a.m. to 7:44 a.m. The days are getting shorter, to be sure, just not on the back end.
By the time we get to the solstice, sunset falls three minutes later than it does right now (4:44 p.m. to be precise), but sunrise doesn't take place until 7:48 a.m. In other words, the shortest day of the year isn't the earliest sunset of the year. If you wake up at 8:00 a.m., your winter solstice is right now.
This astronomical curiousity has to do with the discrepency between our clocks and the sun. Here's how EarthSky explains it:
"The exact time of solar noon, as measured by Earth’s spin, shifts in a seasonal way. If you measured Earth’s spin from one solar noon to the next, you’d find that – around the time of the December solstice – the time period between consecutive solar noons is actually half a minute longer than 24 hours.
So – two weeks before the solstice, for example – the sun reaches its noontime position at 11:52 a.m. local standard time. Two weeks later – on the winter solstice – the sun reaches its noontime position at 11:59 a.m. That’s 7 minutes later."
This variance results in a later time on the clock for both sunrise and sunset, which is why the earliest sunsets precede the solstice.
The point of all this? Now's the best time of the year to wake up early, lest your day feels like it's slipping (sliding) away.
by Derek Flack via blogTO
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