碎片生碎片，因为每次碰撞产生更多的碎片——这就形成一种叫“凯斯勒综合症”的现象，也就是美国物理学家唐纳德·凯斯勒在上世纪七十年代创立的一种假说。

And junk begets junk, as each collision creates more fragments-a phenomenon known as the Kessler syndrome, after Donald Kessler, an American physicist who postulated it in the 1970s.

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“单单这两起事件就将在地球轨道上碎片的数量增加了一倍，并彻底抹煞了我们在过去25年所做的全部工作，”研究带头人凯斯勒·唐纳德说。

"Those two single events doubled the amount of fragments in Earth orbit and completely wiped out what we had done in the last 25 years," said Donald Kessler, who led the research.

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