Description: 时区是指使用统一标准时间的一个区域。我们对时间的度量与地球自转有关。特别是正午时刻，与太阳在天空中的最高位置有关。当地正午时间在很大程度上取决于经度：位于东边的观察者会比西边的观察者更早看到太阳升起并到达正午。位于同一经度的所有地点都有相同的当地正午时刻，因此原则上，我们可以为所有这些地点定义一个共同的时间标准。实际上，统一时间是为一定经度范围、一个国家或一个国家的一个地区定义的。对于大多数地点而言，当地正午接近该时区的官方正午，但略早于或略晚。在这种情况下，官方时间的差异几乎总是整数小时（尽管有些特定的时区偏离了这一情况，例如相差半小时）。

Related Terms:

• Longitude
• Sun Path (Day Arc)
• Time

Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher
The translation of this term and its definition is still awaiting approval

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