Why does leap year occur?

Question

What would happen if it wasn't observed and accounted for on every fourth year of the calendar?

Answer 1

because the actual lenght of time is for the earth to complete one orbit around the sun is actually about 365.25 days. for simplicity it's easier to have 3 365 day years and 1 366 day years.

Answer 2

Our calendar would be too short by a day every four years, and the spring and fall equinoxes would appear later and later in the calendar year.

For a complete explanation, see:

http://www.timeanddate.com/date/leapyear.html


The earth's orbit around the sun actually takes 365.2422 days, not the 365 days we have in our calendar.

So every four years, an extra day is added to account for the 0.2422 days of additional time.

However, 4 x 0.2422 = 0.9688, not one, so adding a leap day every fourth year is slightly too MUCH time.

Over the course of 400 years, 100 leap days are too many, and 97 leap days every 400 years was settled upon.

Every year that ends in 00 is not a leap year, except if the year is evenly divisible by 400.

1700 = not a leap year
1800 = not a leap year
1900 = not a leap year
2000 = leap year


Even this scheme does not exactly match the earth's year, because 97 leap days is slightly more than the 96.88 leap days needed every 400 years. So adjustment might be needed in three thousand years or so.

No one is sure, because the eccentricity of the earth's orbit changes (from more elliptical to more circular and back), and the orbit itself precesses. The earth's axis precesses like a top, the earth's rotation is slowing down, the moon is gradually receding from the earth, etc. What this natural variance in the earth's year will amount to in three thousand years is unknown.

Answer 3

One year i.e the time taken by the earth to complete one revolution of the sun takes 365.25 days. So after every fourth year that 1/4 of a day is accounted by adding one extra day in Feb. That is when a leap year occurs.
It is like adjusting ur books of accounts. Technically nothing will go wrong but say after 120 years we'll have I extra month in hand & that means an year with 13 months!

Answer 4

A solar year, i.e. the time needed for the earth to make an orbit around the sun, is not a round 365 days but a little more, 365 and a quarter (1/4th) of a day. Since it is convenient to have an integer figure for the number of days in an year, the correction is applied once in four years by adding a day to the shortest month, February.

If the rotation is 360 days, we could have made 12 months of 30 days. But since it is more, we needed to distribute the 5 extra days among the months.

Answer 5

A bissextile year occurs each 4 years. the reason of this isn't because the earth spins speedier once each 4 years, that's because in line with annum has about 365.25 days (3 hundred sixty 5 and a quarter). So each 4 years, we upload an more beneficial day to the year so as that we do not bypass any days.

Answer 6

Technically a year is 365.25 days long.

Therefore every 4 years we add up the (4 x 0.25 days = 1 day) to get the extra day - thats the simple way of explaining it anyway.

Answer 7

To put is simply, adding that one day every four years keeps in seasons on tract. If we didn't do that then eventually, then fall would become summer, and winter would be fall, etc.