Universal Time (UT or Z) 1
Universal Time (UT or Z) 1 :
The correct name for the time system previously called Greenwich Mean Time (GMT): the standard time at longitude 0º. Universal Time is five hours later than Eastern Standard Time in the U.S. It is always stated on the 24-hour clock; thus an event occurring at 1:26:15 pm Eastern Standard Time occurs at 18:26:15 UT (five hours after 13:26:15). Technically, the time shown on clocks is figured from Coordinated Universal Time (UTC), an international system of time measurement regulated by very precise atomic clocks. From time to time (either on June 30 or December 31), UTC is adjusted by the addition of a "leap second". This event, widely reported in the press but poorly understood by the public, keeps UTC within 0.9 seconds of mean solar time at longitude 0º as measured by the Earth's slightly uneven rotation. See: day [2] for additional information
