But 50 years later, it emerges that the momentous launch was far from being part of a well-planned strategy to demonstrate communist superiority over the West. Instead, the first artificial satellite in space was a spur-of-the-moment gamble driven by the dream of one scientist, whose team scrounged a rocket, slapped together a satellite and persuaded a dubious Kremlin to open the Space Age.
And that winking light that crowds around the globe gathered to watch in the night sky? Not Sputnik at all, as it turns out, but just the second stage of its booster rocket, according to Boris Chertok, one of the founders of the Soviet space program.
Chertok couldn't whisper a word about the project through much of his lifetime. His name, and that of Sergei Korolyov, the chief scientist, were a state secret. Today, at age 95 and talking to a small group of reporters in Moscow, Chertok can finally give full voice to his pride at the pivotal role he played in the history of space exploration.
As described by the former scientists, the world's first orbiter was born out of a different Soviet program: the frantic development of a rocket capable of striking the United States with a hydrogen bomb.
Because there was no telling how heavy the warhead would be, its R-7 ballistic missile was built with thrust to spare -- "much more powerful than anything the Americans had," Georgy Grechko, a rocket engineer and cosmonaut, said.
The towering R-7's high thrust and payload capacity, unmatched at the time, just happened to make it the perfect vehicle to launch an object into orbit -- something never done before.
When the warhead project hit a snag, Korolyov, the father of the Soviet space program, seized the opportunity.
The launch was first scheduled for Oct. 6. But Korolyov suspected that the U.S. might be planning a launch a day earlier.
Korolyov was taking no chances. He immediately canceled some last-minute tests and moved up the launch by two days, to Oct. 4, 1957.
Soon after blastoff from the arid steppes of the Soviet Republic of Kazakhstan, the satellite sent out what would be the world's most famous beep. But the engineers on the ground didn't immediately grasp its importance.
"At that moment we couldn't fully understand what we had done," Chertok recalled. "We felt ecstatic about it only later, when the entire world ran amok. Only four or five days later did we realize that it was a turning point in the history of civilization."
The first official Soviet report of Sputnik's launch was brief and buried deep in Pravda, the Communist Party daily. Only two days later did it offer a banner headline, quoting the avalanche of foreign praise.
Pravda also published a description of Sputnik's orbit to help people watch it pass. The article failed to mention that the light seen moving across the sky was the spent booster rocket's second stage, which was in roughly same orbit, Chertok said.
The tiny orbiter was invisible to the naked eye.
In the end, it was the Americans who won the race to the moon, nearly 22 years later.
"We wouldn't have been the first on the moon anyway," Grechko said. "We lost the race because our electronics industry was inferior."