Galactic calendar

The Galactic Calendar is the standard measure of time in the galaxy, and is based on the solar cycle of Coruscant, as the capital of the Galactic Republic. The calendar year is measured relative to the Treaty of Coruscant, either in years After the Treaty of Coruscant (ATC), or years Before the Treaty of Coruscant (BTC).

Time Measurement
The calendar was based on the size and rotation of the planet Coruscant. It was a luno-solar calendar based both on Coruscant's orbit around its sun, and the orbit of its primary satellite Centax 1. The standard unit of time was the standard second. Sixty standard seconds made up each standard minute, and sixty minutes made up each standard hour. Each day consisted of 24 standard hours. A standard week was 5 standard days, and each month was seven weeks. (Making 35 standard days each month.) A standard year was 368 days, composed of ten months, three fete weeks, and three holidays. As the Hyperdrive Theory allowed space travelers to bypass relativity, a single duration of time passed at all locations equally over a given interval.

In the galaxy:


 * 368 days=1 year
 * 60 seconds=1 minute
 * 60 minutes=1 hour
 * 24 hours=1 day
 * 5 days=1 week
 * 7 weeks=1 month
 * 35 days=1 month
 * 10 months + 3 festival weeks + 3 holiday days=1 year

Player Reference
Star Wars: Darkness and Light began set in the year 2153 ATC, which is likely more familiar to many as the year 1500 BBY (Before the Battle of Yavin). When referencing events in one of these systems, players should be sure to note that as ATC increases, BBY decreases. All in-character references should avoid usage of the BBY measurement.

Some important dates, in both ATC and BBY, for reference:


 * Founding of the Galactic Republic: 21,400 BTC or 25,053 BBY
 * Jedi Civil War: 306 BTC or 3959 BBY
 * Treaty of Coruscant: 0 ATC or 3653 BBY
 * Fourth Great Schism: 1653 ATC or 2000 BBY
 * Battle of Malrev IV: 1903 ATC or 1750 BBY
 * Darth Pravus becomes Emperor: 2146 ATC or 1507 BBY
 * Vlad Von Drake II becomes Emperor: 2153 ATC or 1500 BBY