What is the Difference Between Julian and Gregorian Calendar?

The Julian and Gregorian calendars are both solar calendars that focus on the 365-day movement of the Earth around the sun, but they have some differences in their definitions and leap year systems. The main differences between the Julian and Gregorian calendars are:

1. Definition of a Year: The Julian Calendar defines an average year as 365.25 days long, while the Gregorian Calendar defines an average year as 365.2422 days long.
2. Leap Year System: Both calendars use leap years, but the Julian Calendar adds a day to the calendar every 4 years, while the Gregorian Calendar does the same, except when the year is divisible by 100 and not divisible by 400, in which case the leap year is skipped.
3. Level of Accuracy: The Julian Calendar is off by 11 minutes every solar year, while the Gregorian Calendar is only off by 26 seconds every solar year.

The Julian Calendar was introduced by Julius Caesar in 46 BCE and was used until the mid-1500s, when Pope Gregory XIII introduced the Gregorian Calendar in 1582 to correct the cumulative effect of the Julian Calendar's errors. The Gregorian Calendar has gradually been adopted by most countries over time, but some Eastern Orthodox churches continue to use the Julian Calendar for religious purposes. The current discrepancy between the Julian and Gregorian calendars is 13 days, but the difference will increase to 14 days in 2100.

Comparative Table: Julian vs Gregorian Calendar

The Julian and Gregorian calendars are two different systems used for measuring time. The Julian calendar was introduced by Julius Caesar in 46 BC, while the Gregorian calendar was established by Pope Gregory XIII in 1582 as a revision to the Julian calendar. Here are the main differences between the two calendars:

The difference between the two calendars increases by three days every four centuries. The Julian calendar is still used by some Eastern Orthodox churches for religious purposes.