"Leap Year" is a human invention. We made it up in order to keep our calendar in sync
with the seasons.
The seasons take 365 and 1/4 days to repeat. But if we tried to put a quarter-day in our
calendar, things would really get seriously messed up.
So instead of putting an extra quarter-day in the calendar every year, we put an extra whole day
in it every fourth year, which is exactly the same thing.
If we didn't do that, then each season would creep 25 days earlier every century. If Winter (in
the northern Hemisphere) started on the correct date at the time of the American Revolution,
then by now, Winter would be starting on October 26 instead of December 21.
365 Days (one year) 366 days in a leap year
366 days
One year........ + 1 day for leap year!
365.25 days or 1 year. The .25 is why we have a leap year every 4 years.
365.25 days. We have a leap year every 4 years to balance the time.
365 days or 366 on a leap year
365 days, 366 on a leap year.
365 1/4 days. Resulting in a leap year every fourth year.
365.24 days is roughly how long it takes the Earth to revolve around the Sun. For convenience we use a "year" of 365 days with" leap years" of 366 days.
An Earth year takes approximately 365.25 days to complete one orbit around the Sun. This is also why we have a leap year every four years to account for the extra quarter of a day.
The calendar year is 365.2425 days, which comes from there being 97 leap years in a cycle of 400 years.
The Earth takes approximately 365.25 days to orbit around the Sun once, which is why we have a leap year every four years to account for the extra quarter day.