NASA launched Telstar 1, the world’s first active communications satellite.

Telstar 1 was developed and operated jointly by NASA and AT&T. While it wasn’t the first communications satellite ever launched, it was the first to amplify signals in space before sending them back to earth. This made it the first satellite to transmit TV signals between Europe and the United States. After seven months in orbit, it was rendered useless by high-altitude nuclear tests.

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