Office of the Chief
Inter-Agency Memorandum
To: BPRD Library and Archives Dept.
March 25, 2410

Chief Librarian Euryale wrote:
>Gryphon wrote:
>>Any other questions, just let me know.
>
>I've got some documents here that claim the current year is "Chun Tai 139",
>not 291 ASC. What's with that?

Oh, right, the eras! I forgot about the eras.

There are two year-counting systems in official use in most of Dìqiú. The civil calendar, which is the one most everybody uses in virtually all aspects of day-to-day life, reckons what year it is based on a historical event called "Sozin's Comet" (hence ASC, "After Sozin's Comet"), which was the appearance of an astrophysical phenomenon nearly 300 years ago that precipitated a devastating world war. Not the most auspicious of starting points for a calendar, but you have to admit it is the kind of thing that sticks in people's minds. It was called Sozin's Comet because that was the name of the Fire Lord at the time, and he started the war.

(N.B. You may run across references to the phenomenon itself as Sozin's Comet in older documents, but be aware that this is a deprecated usage. Dìqiú's International Astronomical Union named the actual object "Comet Zuko", after a later Fire Lord, in 201 ASC. In modern parlance, "Sozin's Comet" refers only to the appearance of Comet Zuko in 1 ASC.)

Anyway, that's ASC. The nomenclature you're running into there is an older system of dating that's basically only used in extremely formal/official/ceremonial contexts nowadays. It works not unlike the way imperial/regnal eras worked in ancient China, pre-Contact Wars Japan, and the Salusian Empire before Jerka, except the person it's linked to isn't a ruler, it's the Avatar. Each era corresponds to the life of a single Avatar - the Chun Tai era is Korra's, her predecessor Aang's was called Ri Wu, and so on. The year Korra was born, SY 2372/153 ASC, was both Chun Tai 1 and Ri Wu 167 (Aang lived to be 166, and there's no zero year in Avatar eras).

Important note: What era year it is at any given moment is not connected to when in the year the Avatar's birthday is. It's always one more than what the Avatar's age will be on his or her birthday in that year. For example, Korra's 138th birthday is next month, but it's been Chun Tai 139 since January 1. The only exception to this rule is in the years when there's a changeover. In that case it's traditional to call April 13, 2372 the last day of Ri Wu 167 and April 14 the first day of Chun Tai 1. After that, they fall in line with the civil calendar for sanity's sake.

Sorry about that, Eury, I completely forgot to include that in your copy; it never occurred to me that you'd naturally be looking at much older and/or more esoteric docs than the Babylon Foundation's people. Nowadays, the only people in Dìqiú who still use the era years on a regular basis, and not just when they're trying to be impressive, are very-high-level bureaucrats in the Earth Kingdom and United Republic, and of course the Great Spirit Library, which is presumably where you ran into it.

Speaking of which, Korra asked me to ask you to please not turn Wan Shi Tong to stone again, regardless of provocation. That'll be hard, I know - I am well aware that provocation is one of his many very well-established core competencies - but he can't be replaced and we really don't need another interplanar diplomatic incident of that caliber again this decade.

Thanks and I hope this clears it up,
--G.