Sometimes the UTC time is also called 'Zulu time', simply for the fact that time is briefly referred to as 'Z time' in naval-air navigation and the letter Z is articulated as 'Zulu' in the NATO phonetic alphabet. This second is called 'leap second' and its calculation starts from 1972. It is typically taken off one second every 36 months, although of course this is not a certain and scientific rule.

With this change in duration of minutes, you do so in order to keep the delay between the UTC and the 'earth time' within 0.9 seconds: when needed (typically on June 30th or December 31st), on the recommendation of the International Earth Rotation and Reference Systems Service (IERS, which deals, among other things, the measure of Earth's rotation), is considered a minute with duration of 59 or 61 seconds. On last June 30th 2015 a minute with 61 seconds has been considered: this variation depends on the time of rotation of the earth around the sun, which, due to fluctuations in its velocity, is not constant. Simplifying, the UTC time divides time into days, hours, minutes and seconds, but while one day is always of 24 hours and one hour always of 60 minutes, a minute, while almost always consists of 60 seconds, sometimes it can be a period of 59 or 61 seconds. It is similar to Greenwich Mean Time (GMT), but unlike this time, it is not based on the time of rotation of the Earth, but on measurements made by atomic clocks that are most accurate and above all more stable over time. UTC time - Coordinate Universal TimeĬoordinated Universal Time is the time zone '0' from which all other time zones around the world are then calculated. There are many standard definitions of the time, but the main four are: UTC, GPS, LORAN and TAI. Typically this time is maintained by specific atomic clocks and has a satellite distribution. A lot of the current technology to work properly requires a very precise definition of the time.

Current utc time zone