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Dennis Murphy

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Why are leap years used?
Jamie Reading, Corner Post Staff

February 27, 2004 - With this year being a leap year, does anyone really know why there is one, and when does it occur?

A leap year is when there are 29 days in February, one more day than normal. On leap years, February has five Sundays, in which it starts on and ends.

To figure out what year is going to be a leap year gets pretty tricky. The first rule is that every year that is divisible by four is a leap year, and the second rule is that every year divisible by 100 is not a leap year unless the year is also divisible by 400, then it is still a leap year. Confused yet?

Leap years are needed so that the calendar is in alignment with the earth's motion around the sun. Using a calendar with 365 days would result in an error of up to six hours per year. In 100 years, this calendar would be about 24 days ahead of seasons.

By adding leap year approximately every four years, this difference between the calendar and the seasons can be significantly reduced, and the calendar will follow the seasons much more closely than without the leap years.

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