what date does the sun start rising earlier?

Oh hiking guru …

Well, the shortest day of the year is December 21st in the northern hemisphere.

Must be that the sun starts rising earlier December 22nd.

Right ??


Wrong.

In Saskatoon, Canada the sun rose at 9:14 AM on December 22nd.

Then later for the next couple of weeks.

It did not start rising earlier until Jan 8th.

This little known fact has something to do with the Equation of time.

Warren Long noticed as he leaves for work around that time on a bike. And was wondering why he was not seeing sunrise sooner.

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3 thoughts on “what date does the sun start rising earlier?

  1. The latest sunrise here is usually Jan 4, while the earliest sunset is around Dec 7; they average out to the shortest day being around Dec 21. The same is true around the Summer Solstice. The graph of this is an analemma. Your friend was quite observant, because the change in day length is minimal around each solstice, greatly accelerating about two weeks before and after each solstice.

  2. Is this because of the latitude? For instance, in norther hemisphere winter, at that level, it’s closer to the arctic cirlce and the light directed there reaches it differently because of earth’s rotation on an angle. Or am I missing something more profoundly simple?

    @Buzz: Your notes and observations are alwasy insightful!

    –Andrew

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