Today is our extra day. February 29th means it’s a Leap Year.
Do you know why we get the 366th day, every four years?
In short, sun and moon cycles need to be synced up with the Earth’s rotation, every once in a while.
Julius Ceasar consulted mathematicians and philosophers, to establish the extra day, every four years.
The Julian calendar was replaced with the Gregorian calendar in the 1500s. In 1582, Pope Gregory XIII also consulted with astronomers, mathematicians, and religious scholars, to put us on our current calendar path.
Years that are divisible by 4 get leap years. However: Every three out of four turns of the century do not get leap years. That means: We got one in 2000… But we will not have one in 2100, 2200 or 2300.