2016 is Leap Year. In February 2016 we enjoy an extra day February 29
Leap Year
- A normal year has 365 days.
- A Leap Year has 366 days (the extra day is the 29th of February).
How to know if a year is a Leap Year:
 | Leap Years are any year that can be evenly divided by 4 (such as 2012, 2016, etc) | ||
 | except if it can can be evenly divided by 100, then it isn't (such as 2100, 2200, etc) | ||
| except if it can be evenly divided by 400, then it is (such as 2000, 2400) | ||
Why?
Because the Earth rotates about 365.242375 times a year ...
... but a normal year is 365 days, ...
... so something has to be done to "catch up" the extra 0.242375 days a year.
- So every 4th year we add an extra day (the 29th of February), which makes365.25 days a year. This is fairly close, but is wrong by about 1 day every 100 years.
- So every 100 years we don't have a leap year, and that results in 365.24days per year (1 day less in 100 year = -0.01 days per year). Closer, but still not accurate enough!
- So another rule says that every 400 years is a leap year again. This gets us365.2425 days per year (1 day regained every 400 years = 0.0025 days per year), which is close enough to 365.242375 not to matter much.
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