February is known for many things, one of which is being the shortest month of the year.

Many people do not give much thought to whether or not February has 28 or 29 days. But February bears the unique distinction of being the only month on the calendar that does not always have the same number of days.

Known as a ‘leap day,’ the 29th day of February helps to synchronize the calendar to Earth’s orbit. According to EarthSky, which reports on astronomy and other cosmos-related information, Earth’s orbit around the sun takes approximately 365.25 days. That extra .25 creates a need for a leap year every four years; otherwise, the calendar, which is faster than the actual solar year, would drift from what is actually occurring with the orbit. After four years, it would be off by one day, or 25 days after 100 years. If no corrections were made to the calendar, the seasons might become misaligned. After 300 years, January 1 would arrive in autumn.

Julius Caesar, at the advice of Sosigenes, an Alexandrian astronomer, was responsible for adding a leap day to February to compensate for Earth’s rotation after the original Roman calendar kept slipping out of alignment. During his reign, Caesar first implemented a 445-day calendar year in 46 BCE to bring the calendar back into alignment. Roman officials called it annus confusionis. To limit future headaches, the work-around was to simply add a leap day to February once every four years. The Julian calendar wasn’t exact to the solar year, but it was much closer than the previous Roman calendar.

The Gregorian calendar, revised by Pope Gregory XIII in 1582, further adapted the calendar and the leap days. All leap years are divisible by four. That is why 2020 will include a leap day on February 29.

People can utilize the extra day in 2020 (yes, 2020 is a leap year) in various fun ways. In addition to learning more about leap years and astronomy, try these entertaining ideas.

Take a day off of work and spend it relaxing or engaging in a favorite hobby. Be reminded that leap years also coincide with U.S. Presidential elections, and it will soon be time to vote. Check out the celebrities who were born on February 29 and only get a true birthday every four years. Rapper Ja Rule, motivational speaker Tony Robbins, actor Antonio Sabato, Jr., swimmer Jessica Long, and football player Eric Kendricks are some of the notable people born on February 29. Buy a gift for yourself or others on leap day and make it a tradition of going the extra mile to love and pamper. Realign your life like the calendar is being realigned by focusing on organization or personal finances.