translation.en: But then a big difference happened about 50 years ago, after Sputnik was launched. We launched the first American satellite, and that's the one you see on the left in there.
translation.zh: 不过50年前，发生了一件不同凡响的事， 苏联人造卫星发射后。我们发射了第一颗美国卫星， 卫星就在左边的照片里。