Some things about leap years are widely known. Everyone knows that leap year comes every four years and that it tacks on an extra day to February. Most people know that the extra day has to do with astronomy and is necessary in order to keep the years aligned with the stars.

Somethings, on the other hand, are not well known. Have you ever wondered how it came about? Well the earth takes 365.2422 days to complete a rotation around the sun. Before leap years, the roman calendar was 355 days long and every 2 years, an extra 22 days were added to make up for lost time. This was a really messy system if you ask me. Apparently Emperor Julius Caesar though so too because he ordered his astronomer to fix the mess. Thus, the leap year system was born. 

Have you ever wondered why February was selected to receive the extra day? February was picked because it is the shortest month with only 28 days in a normal year. The answer is somewhat obvious, but it also poses another question. Why is February abnormally short while all of the other months either have 30 or 31 days? During the reign of Emperor Caesar Augustus, the month of August (named after his highness) actually had 29 days and February had 30. Being an emperor Caesar Augustus ordered two extra days added to August so that it was at least equal with July (a month named after his predecessor Julius). In order to do so, two days had to be stripped from another month. Guess which one lost out? You got it, February.

Another bit of leap year trivia is about when it occurs. While it is assumed leap year happens every 4 years, that is not always the case. Any year divisible by 100, but not divisible by 400 is not a leap year. So, 2000 was a leap year, but 2100 will not be one even though it will be a fourth year. This rule was made because the every 4 years concept wasn't that mathematically exact.

TB

Astronomy compels the soul to look upwards and leads us from this world to another.
-Plato