Why is there sometimes 366 days in 1 year?

Answer 1

It wasn't a matter of changing the years. It was a matter of reckoning time in such a way that we could reliably set the beginnings of the seasons. We needed to know this so that we could begin planting at the right time, etc. 360 days is a horribly inaccurate estimate, and the seasons would go haywire if we attempted to use such a year.

Answer 2

A leap year, which has 366 days, occurs every four years to account for the extra part of a day that is not accounted for in our standard 365-day calendar. This adjustment helps keep our calendar in alignment with the Earth's orbit around the sun.

Answer 3

Because of the simple reason that's the way the ancient Romans made our calendar. They basically decided on which months were how many days, and how many days were in the calendar. When we adopted the ancient Roman calendar, we adopted the concept of a 365-day year.

Answer 4

Best current measurements suggest that it takes about 365.25 days for the earth to go round the sun. Hence the leap year every 4 years to correct the calander by adding an extra day onto the end of February.

Answer 5

Leap Years are needed to keep our calendar in alignment with the Earth's revolutions around the sun. It takes the Earth approximately 365.242199 days - or 365 days, 5 hours, 48 minutes, and 46 seconds (a tropical year) - to circle once around the Sun.

Answer 6

Because it does. There isn't any fundamental reason it should; it's just that the Earth happens to be at a particular distance from the Sun, and the orbital period for an object at that distance is about 365 days (actually slightly longer, which is why we need to add leap years every so often).

Answer 7

That's not the correct number of days!

There are 365 usually and 366 in a leap year.

The length of the year is based on the time it takes the Earth to orbit the Sun.

That time is about 365 and a quarter days.

Answer 8

The Earth orbits the Sun once in about 365.24 days.

So, technically, there should be 365.24 days in every year, but it's tough to count a quarter of a day. So we count 365 days for three years, and then add a "leap day" every 4 years.

That would work perfectly if the orbit period were 365.25 days, but it isn't; it's 365.24 days.

So, every hundred years, in the "century years" like 1900 or 2100, we skip the leap day itself.

But in century years that are divisible by 400 without a "remainder", like year 2000, we keep the leap day.

That makes everything work out OK...nearly!

Answer 9

It's generally not useful to ask "Why?" about physical facts. It takes the Earth 365.24 days to orbit the Sun because that's the orbit that we are in. If we were in a different orbit, then the duration of the year would be different, and the Earth would be different, and WE would be different - because we evolved on THIS planet, HERE, the way things are NOW.

Answer 10

The best answer is: Because the earth happens to be about 93 million miles from

the sun, and that's how long it takes to go around the sun when you follow a path

that's about 93 million miles from it. It doesn't make any difference at all how big or

how heavy you are, only how far your path is from the sun. That's how gravity works.