Time Zone

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The World Time Zones

A geographical region in which one time is valid for all places. There are 24 time zones on earth. They were established in 1884 and there is usually a difference of one hour between one time zone and the next one. In theory, the time zones are all 15 degrees of longitude in size, but in practice the division has been adapted to political borders around the world. In each time zone a standard local time is based around a particular degree of longitude. For example, Middle European Time (MET) is concurrent with the local time at 15 degrees East of longitude. In Germany Goerlitz is located at this degree of latitude.

When calculating a horoscope, the local time always has to be translated into Greenwich Mean Time at zero degrees of longitude, the prime meridian, which is also referred to as universal time.

The time zone is not the only significant factor when calculating a horoscope - it is also necessary to take into account whether or not Daylight saving time was in force at the time of the birth. The time in some countries may also deviate from the standard time in the zone in which they are located. For example, double summer time was in force during (and for some time after) the Second World War in Germany.

The Most Important Time Zones

Greenwich Mean Time is the standard zone and starting point for all other time zones. The deviation from Greenwich Time is given after the international abbreviation for each time zone:

  • GMT (0) Universal Time, also: Greenwich Mean Time, Greenwich Time
  • WET (0) Western European Time
  • WAT (-1) West African Time
  • AT (-1) Azores Time
  • AST (-4) Atlantic Standard Time
  • EST (-5) Eastern Standard Time
  • CST (-6) Central Standard Time
  • MST (-7) Mountain Standard Time
  • PST (-8) Pacific Standard Time
  • YST (-9) Yukon Standard Time
  • AHST(-10) Alaska-Hawaii Standard Time
  • CAT (-10) Central Alaska Time
  • HST (-10) Hawaii Standard Time
  • NT (-11) Nome Time
  • IDLW(-12) International Date Line West
  • CET (+1) Central European Time
  • MET (+1) Middle European Time
  • EET (+2) Eastern European Time
  • BT (+3) Baghdad Time
  • WAST (+7) West Australian Time
  • CCT (+8) China Coast Time
  • JST (+9) Japan Standard Time
  • EAST(+10) East Australia Time
  • GST (+10) Guam Standard Time
  • IDLE(+12) International Date Line East
  • NZST(+12) New Zealand Standard Time