To measure astronomic distances one takes as a unit that distance which light travels in a year.

为了度量天文距离，人们把光在一年中走过的距离当作一个距离单位。

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To measure astronomic distances one takes as a unit that distance which light travels in a year.

为了度量天文距离，人们把光在一年中走过的距离当作一个距离单位。

youdao