Question: Why does the new year “start” on January 1st, rather than some other date? — RA, Greenwich, England
Answer: That’s a good question, the answer to which goes back many Moons. Fact is, the start date of the year differs among cultures. There’s currently about 40 different calendars in use around the globe. China, for example, celebrates the new year on a variable date between January 21 and February 20.
Before you continue, take a look at this Sky Lights post. The Earth orbit animation might help clarify my explanation here. It’s mostly about the astronomical difference between a year and a day.
Western society uses the “Gregorian Calendar,” decreed by Pope Gregory (with the help of his Jesuit astronomers) way back in 1582 AD. It’s a modified version of the “Julian Calendar,” decreed by Julius Caesar in 45 BC. Both calendars used January 1st for the start of their new year.
Of course, whatever date one chooses to start the year, one (1) year is defined as the amount of time it takes Earth to complete one (1) orbit around the Sun. The calendar start date was an arbitrary choice made by Julius Caesar. Some historians say his ...