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# Why do we have a leap year?

Updated: 8/18/2023

Wiki User

6y ago

It takes the Earth slightly more than 365 days to revolve around the Sun. So we add another day to our year every fourth year, to keep the seasons more closely aligned with the calendar.

It takes the Earth about 365 1/4 days to orbit the Sun. It is not possible to include this as a fractional day each year, so every 4 years an extra day is added at the end of February which is called a leap day, February 29th.

Even so, there is not quite 1/4 extra day, so in years ending in 00 that are not divisible by 400, the leap day is omitted. 1900 was not a leap year, and 2100 will not be one.

Because in really takes 365 Days and 6 hours for the Earth to revolve around the Sun... so they add the extra 6 hours and after 4 years it adds up to 24 hours...thus making February 29th possibleBecause the earth takes 365 and 1/4 days to revolve once around the sun,

and it's much cleaner and makes a lot more sense to make the calendar

1 day longer every 4 years than to try to make it 1/4 day longer every year.

Wiki User

9y ago

Wiki User

6y ago

The actual solar year, the time it takes to go around the sun one time is just a little longer than 365 days. Leap year makes up for that.

Since it takes 365 and 1/4 days for the earth to revolve around the sun, one day needs to be added every four years (Feb. 29th) so that the calendar and seasons don't get out of whack. (Otherwise, after about 730 years, summer would be in what are now the winter months, and winter would be in what are now the summer months.)

And because there is really 365 days, 6h, 9mins so that 6hrs 9mins turn into a whole day
Roughly speaking it takes the Earth 365 and a quarter days to circle the sun, which is called a year. So every 4 years we need the extra day to stop the calendar from getting out of line with the sun. Certain days in the calendar are linked to the sun eg it should be overhead at noon on the vernal equinox (Mar 20) at the Tropic of Cancer. It actually takes 364 1/4 days for the sun to rotate the earth. So, every four years we throw in an extra day to make up those four quarter days. It actually takes the Earth 365.25 days to orbit the Sun, so an extra day is added every four years to compensate.
Earth travels around the sun once (approximately) every 365.25 earth days. A quarter day cannot be added into a year, therefore an extra day is added (as February 29th, Feb. being the shortest month) every 4 years. That year is called a leap year due to the leap of 4 quarter days to 'catch up,' causing a 366 day year.

1. The addition of a day, Feb. 29th, to the Gregorian calendar, every 4th year to compensate for the difference between the calendar year and the actual orbital year. The calculation to identify these years is: years whose last two digits are evenly divisible by four, except for centenary years not divisible by 400.

2. The addition to a given year, of a day or month for any calendar. Leap years are necessary because the time it takes the earth to orbit the sun is not an exact multiple of a day. It takes roughly 365.22 days per orbit. The calendar ordered by Julius Caesar (Julian Calendar) rounded that down to 365. Of course, that's not nearly enough; those extra 22/100 of a day each year add up pretty quickly, which is why every fourth year of the Julian calendar has 366 days. If the earth's orbit took 365.25 days, that would have been good enough. In fact it was considered good enough for over a millennium. Eventually the offset caused by that extra 3/100 of a day per year accumulating for many hundreds of years could no longer be ignored, so Pope Gregory ordered a refinement of the Julian calendar (the Gregorian Calendar, which we use today). The Gregorian Calendar includes the extra rule that the last year of every century is a leap year ONLY if the year is evenly divisible by 400. the Gregorian calendar has a leap year because every year has 365 days and a quarter of a day so every four years we make up for those quarters by having an extra day which makes a leap year.
there is an extra quarter of a day at the end of a year so every 4 years we put them together to make a whole day

Wiki User

12y ago

A year is defined as the length of time it takes for the Earth to orbit the Sun once. This takes almost exactly 365.25 days. A calendar year is 365 days, so in actual fact every time we celebrate a "new year", we are a quarter of a day behind a real new year. Therefore, every four years we add an extra day to the year to make up for the deficit.

Wiki User

13y ago

Leap years occur because the orbital period of the Earth around the Sun is not an exact multiple of the rotational period of the Earth about its axis relative to the Sun. The rotational period is, on average, 24 hours or 1 day. The orbital period is slightly less than 365.25 days. In fact, that "slightly less" accounts for about 3 days in 400 years, so the century years not divisible by 400 are not leap years.

Wiki User

13y ago

One year is approximately 365 and 1/4 days, and so every four years, they take that quarter of a year and add it up to make one day - February 29th.

Why February has it is probably because it already is the shortest month of the year with only 28 days.

Wiki User

8y ago

it's the other way around, every 4th year is one day longer.

This is because it actually takes the Earth about 365 and a quarter of a day to circle the Sun. If we didn't use leap years to add back a day, eventually the calendar and the seasons would start to drift apart.

(if you look really, really close, there are also leap hours and leap seconds that are added as needed to keep out clocks and calendars in synch with how the planet moves.)

Wiki User

11y ago

It is added to the end of February, the second month of the year.

In a regular year, the day after February 28 is March 1.

In a leap year, the day after February 28 is February 29, and the day after February 29 is March 1.

Wiki User

12y ago

Every year there is an extra quarter of a year (1/4) so every forth year ther add an extra day on the end of Febuary to make up for the last 4 quarter days.

Wiki User

13y ago

February only has 28 day whereas all the others have 30 or 31. Why not give it to February to give him a slight boost every four years so he wont feel like such an odd month out.

Wiki User

6y ago

The Earth does not orbit the sun in precisely 365 days. Adding a Leap Day, February 29, every fourth year is used as a correction.