Why are leap years included in the calendar?

Answer 1

a leap year is february 29th and it appears every 4 years on the gregorian calendar. it exists to keep seasons where they are in relation to the year. because a year is 365.25 days wheras you can only have 365 days in a year, so to account for that .25 they add an extra day every four years.

Answer 2

Leap years are used due to the fact that a year is not exactly 365 days. In reality a year is 365.24219 days, therefore by adding an extra day every four years as the leap year does, the error is almost accounted for. The adopted average for the length of a year is 365.25, which is a slight over correction. This approximation and leap years were introduced by the Julian Calendar which Julius Caesar introduced in 46 B.C.E. His over correction is accounted for by another rule concerning leap years which was introduced by the Gregorian Calendar (instituted by Pope Gregory XIII in 1582 and still in use today). The Gregorian calendar adds 97 leap days every 400 years according the rule that leap days are added to those years divisible by 4, except for years both divisible by 100 and not divisible by 400. For example 1600 was a leap year, whereas 1700, 1800, and 1900 were not, and then 2000 was. The calendar will always be an approximation, but the error involved with the Gregorian Calendar is small: approximately 1 day for every 3,236 years, so we won't have to worry about this error for quite a while, and definitely not in our lifetime.

Another interesting fact regarding leap years is that when Julius Caesar introduced his Julian Calendar in 46 B.C., he stated that a leap year be added every four years (as stated above), but the priests in charge of computing the calendar added these leap years every three years instead of the correct four. This was not noticed until 10 B.C.E., after which a leap was not added until 8 A.D.

Answer 3

Leap years in solar calendars are to make up for the fact that a year is not an exact multiple of a day. Leap years in luni-solar calendars are to make up for the fact that a year is not an exact multiple of a month.

Answer 4

Every four years the calendar has an additional day in February. The original creators of the Gregorian calendar were not exceptionally good in arithmetic.