It happened today.

NASA opens its doors

NACA becomes NASA, one year almost to the day after Sputnik.

Sputnik

A 58-cm sphere and a steady beep. The space age begins over everyone's head at once.

The sound barrier falls

Chuck Yeager's X-1 goes supersonic over the Mojave — the flight-test lineage every spacecraft descends from.

Cassini departs

Seven years to Saturn, a Titan lander riding along.

Venera 4 tastes Venus's air

The first direct measurements inside another planet's atmosphere — mostly carbon dioxide, crushingly dense.

'Oumuamua

The first known object from another star system is spotted racing through ours.