“信使”号探测器在六年半前开始了它的太阳系之旅，直到今年三月十八日才进入水星轨道。

The Messenger began its trip through the inner solar system six and a half years ago, and it entered orbit around Mercury on March 18.

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水手10号只拍到了水星布满陨石坑的表面45%的图片，前三次信使号飞过水星也没能提供所有图片。

Mariner 10 captured just 45 percent of the cratered surface before moving on, and the three previous MESSENGER flybys didn't quite fill in the whole picture.

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