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Earth and Space Sciences · 术语表

什么是 Time zone?

Definition 14.6 Primary & Middle School Earth and Space Sciences · 第 14 章 — Latitude, Longitude and Time Zones

A time zone is a band of the Earth, from pole to pole, where all the clocks show the same time. Ideally, each zone is 15∘15^\circ of longitude wide, so that there are 24 zones, one for each hour; going one zone to the east, the clocks show one hour more.

The 24 ideal time zones, each 15 wide, with the number of hours to add to the time at Greenwich (the black line in the middle). The date line runs along the 180 meridian, which this map cuts in two: it is both the left and the right edge. Roll the map into a tube, and the two red lines become one. The zone on each side of the date line is half a zone wide.
The 24 ideal time zones, each 15∘15^\circ wide, with the number of hours to add to the time at Greenwich (the black line in the middle). The date line runs along the 180∘180^\circ meridian, which this map cuts in two: it is both the left and the right edge. Roll the map into a tube, and the two red lines become one. The zone on each side of the date line is half a zone wide.
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