NASA的航天計劃從來就是一個完成另一個繼續的，航天飛機項目是完成了，取得了成績也有教訓。

來源: 望自遠方於 2013-12-15 19:12:21 [舊帖] [給我悄悄話] 本文已被閱讀：次

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