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• The period within a few weeks of the winter solstice in late December is the darkest time of the year for northern latitudes.
• Not only does the sun traverse its lowest ark across the sky at this time, but in many places the sun sets before the end of the normal workday and rises after many people have already started the daily routines.

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• At latitude 40 degrees north the earliest sunset occurs around December 8 each year,and the latest sunrise occurs around January 5.
• At latitude 40 degrees north the earliest sunrise occurs around June 14 and the latest sunset occurs around June 28.
• Most of us don't like the short period of daylight

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• The changing times of sunrise and sunset are probably more noticeable in the winter months, because sunrise and sunset occur when we are more likely to be paying attention when we are starting our day and during the evening rush hour.

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• Our clocks don't keep up with sun time.
• The changing position of the Sun in the sky over the corse of a day is mainly in affect of the earths rotation on its axis, which is quite uniform to a small fraction of a second.

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