Meridian These are similar to UTM zones. Both apply to large areas based on a line of longitude, both are often left out of field data, and the position is not uniquely defined without them!

子午线与通用横向麦卡托分区相似，同样以一条经线为基础询问大区域，同样通常忽略现场数据，且位置不是绝对的。

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Greenwich thus became established as the location of the prime meridian of longitude, and the base line for calculating time zones around the world.

由此格林威治不仅作为起初子午线的所在地，也成为全球计算时区的基准线。

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The Greenwich meridian was adopted in 1884 by the International meridian Conference as the line with zero degrees of longitude.

国际本初子午线大会于1884年把横过英国格林尼治天文台的一条经线定为参考线，在该线上经度为零。

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