On October 4, 1957, an R-7 rocket lifted off from the Baikonur cosmodrome in the Kazakh SSR and put Sputnik 1 into an orbit that took 96 minutes to complete. The satellite was a polished aluminium sphere 58 centimetres across, weighing 83.6 kilograms, with four wire antennae and a transmitter sending a beep on two frequencies that any radio amateur could pick up. It transmitted for 21 days, until the batteries went, and burned up re-entering on January 4, 1958.
It was a substitute. Sergei Korolev's design bureau had been working on Object D, a much larger scientific satellite, and had fallen behind, and when it became clear the Americans were close to launching something for the International Geophysical Year, Korolev got permission to fly a simplified version instead. Sputnik means fellow traveller.
The rocket was the point. The R-7 was the world's first intercontinental ballistic missile, tested successfully in August 1957, and everyone in the business understood what that meant: a rocket that could throw 83 kilograms into orbit could throw a warhead at an American city. That is what turned a beeping ball into a political event.
The American reaction was out of proportion to the object and proportional to the rocket. Eisenhower played it down and was criticised for it, and the Gaither report, leaked in November, described a missile gap that did not exist in the direction people assumed. Congress passed the National Defense Education Act in 1958 and put money into science teaching. NASA opened on October 1, 1958. Explorer 1, the first American satellite, went up on January 31, 1958.
The satellite did one scientific thing of value. By tracking the change in its radio signal as it passed through the upper atmosphere, observers could work out the air density up there. Everything else it did was to show that the sky was now a place where states could act. More than 8,000 satellites have been launched since, and that beep is the sound usually used to mark the start of the space age. Korolev died in 1966 during surgery.