Space Exploration Timeline

<see whole timeline
Sep 20, 1956
  –  

Jupiter-C first flight. First rocket to pass the thermopause and enter the exosphere.

At 682 miles (1,098 km) altitude and 3,335 miles range, the 3-stage Jupiter-C breaks both records and achieves MACH 18 velocity.

https://en.wikipedia.org/wiki/Jupiter-C