zone
The nine U.S. time zones, east to west:
Atlantic standard time (AST)
eastern standard time (EST)
central standard time (CST)
mountain standard time (MST)
Pacific standard time (PST)
Alaska standard time (AKST)
Hawaii-Aleutian standard time (HST)
Samoa standard time (UT-11)
Chamorro standard time (UT+10)
Note that for editorial mentions of National Geographic Channel programs, NGP preferred style for time zones in air times is to list Eastern time followed by a slash, then Central time followed by a lowercase "c": 10/9c.