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Why is the Sun up so early on June 14th?

The 2008 Farmers’ Almanac says the earliest sunrise this year will happen on June 14. Why doesn’t this date coincide with the summer solstice on June 20?

The answer is due to in part to the Earth's elliptical orbit around the Sun. The Earth moves faster in its orbit during January (when we're closest to the Sun) than in July, when we're farthest away. Because of this motion, the Sun’s path through the sky, when charted on a day-by-day basis, appears to take a lopsided figure-8 pattern astronomers call an “analemma.” (See the image.)

Because the Sun makes this odd pattern in the sky during the year, it is rarely on the meridian at exactly noon. More often than not, the Sun lines up with the meridian as much as 15 minutes before or after noon. Those who have sundials set up in their gardens are well aware of this discrepancy, known as “The Equation of Time.”

The Sun’s odd looping path also explains why the earliest sunrise – and the latest sunset – fail to exactly coincide with the summer solstice. Instead, the earliest sunrise occurs about a week before the solstice, while the latest sunset occurs about a week after the solstice. On June 20, the solstice, the Sun's position on the analemma is at the very top of the figure-8, whereas on June 14, it's slightly to the right of the topmost position, causing it to arrive at the eastern horizon a little sooner than on June 20. On June 27, on the other hand, it's slightly to the left of the topmost position, causing it to arrive at the western horizon a bit later than on June 20.

A similar effect happens during the winter solstice, when the earliest sunset arrives about two weeks before the December solstice, and the latest sunrise occurs about two weeks after the solstice.

Why two weeks in winter instead of the one in summer? Remember the Earth moves slower in its orbit around the Sun in the summertime because it’s farther away, and faster in the winter because it's closer. In the winter it moves faster, and thus “covers more ground’ in its orbit.