I play flag football with some friends at work every week, and we have been frustrated by increasingly shorter games as winter solstice approaches. We noticed lately that our games have been getting longer, even though we hadn't reached Dec. 21 (shortest day of the year) yet. I told my fellow flag-footballers that this is because the earliest sunset occurs before the shortest day of the year. I thought it had something to do with either Earth's orbit is not being circular (it is slightly elliptical), or the tilt, or obliquity of the Earth's poles with respect to its orbit around the sun.
Well, it turns out I was correct. This page describes how Earth's obliquity and Earth's eccentricity affect the shape of the analemma (the path the sun traces out on Earth over the course of a year).
So, in case you were wondering, the earliest sunset occurs on Dec. 7th. The latest sunrise occurs on January 4th.
Well, it turns out I was correct. This page describes how Earth's obliquity and Earth's eccentricity affect the shape of the analemma (the path the sun traces out on Earth over the course of a year).
So, in case you were wondering, the earliest sunset occurs on Dec. 7th. The latest sunrise occurs on January 4th.
1 comment:
That is correct. Winter solstice marks the shortest day of the year.
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