Astronomical year numbering
Cassini gave the following reasons for using a year 0:
Fred Espanak of NASA lists 50 phases of the moon within year 0, showing that it is a full year, not an instant in time. Jean Meeus gives the following explanation:
Although he used the usual French terms "avant J.-C." (before Jesus Christ) and "après J.-C." (after Jesus Christ) to label years elsewhere in his book, the Byzantine historian Venance Grumel used negative years (identified by a minus sign, −) to label BC years and unsigned positive years to label AD years in a table. He did so possibly to save space and put no year 0 between them.
Numbers in Year Zero
This is a comprehensive list of the numbers of the Year Zero alternate reality game by Nine Inch Nails and 42 Entertainment. The "Year Zero" alternate reality game, and its accompanying concept album of the same name, criticizes the United States government's policies as of 2007, projecting a dystopian vision of its impact on the state of events in 2022. The game has been underway since roughly February 12, 2007 and is expected to continue for approximately eighteen months.