But here we come up against the most difficult of all obstacles to contact with people on other planets — the astronomical distances which separate us.

然而，在和外星人联系中我们遇到的最大困难是分隔我们的天文距离。

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But now, the crystalloid has been detected two astronomical unit distances away from earth, and it is flying to the earth accurately with its precipitous unnatural orbit.

但现在晶体在两个天文单位外被探测到，它沿一条陡峭的绝非自然形成的轨道精确地飞向地球。

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