In this first of five articles, space.com's Andrew Chaikin begins a decade-by-decade look at the 20^th century's most significant developments in space.

When you think of the 1950s, you might recall the decade's contributions to popular culture: Rock n' Roll, hula hoops and horror films featuring a menagerie of giant radioactive beasts. Long after Godzilla is forgotten, however, the fifties will be remembered as the dawn of the Space Age.

At first glance, it might seem that inspiration -- a love of exploration, a fascination with the unknown -- was at the heart of this dramatic change. And it is true that the fifties were ripe with inspiring writings about worlds beyond. A series of articles in Colliers magazine, beginning in 1952, offered fantastic visions of humanity's future in space, written by experts in the field and illustrated with stunning works by such artists as Chesley Bonestell and Fred Freeman. The opening installment in the Colliers series declared, "Man Will Conquer Space Soon."

Such presentations served to raise the American public's awareness that such things were going to happen -- but would they happen as quickly as Colliers promised? In 1952, no one would have guessed that only five years remained before the first Earth satellite would be launched, and only seven before the nation's first astronauts would be named. The reason those developments came as soon as they did -- and the force behind the 1950s' push into space -- was the Cold War.

Growing tensions between the United States and the Soviet Union marked the years after World War 2. Soon after the war ended, both sides engineers who knew how to build large, liquid-fueled rockets. And the U.S. monopoly on nuclear weapons ended in 1949, when the Soviets tested their first atomic bomb. By the early 1950s, the U.S. and U.S.S.R. were working to merge these technologies in a terrible new weapon -- the Intercontinental Ballistic Missile (ICBM).

Until very recently, most historians believed the Soviets got there first.

A brilliant engineer named Sergei Korolev led the Soviet ICBM effort, and his team created a powerful new booster, officially designated R 7, but known to Korolev's team by its Russian nickname Semyorka ("number seven"). It stood almost 100 feet high and developed 880,000 pounds of thrust at liftoff. In August 1957, Semyorka flew to its full range of almost 4,000 miles (2480 kilometers) -- enough to qualify it as an intercontinental rocket. But the dummy warhead at the rocket's nose was destroyed during reentry into the Earth's atmosphere. The Soviets made no mention of mishap in their public statements. However, such problems would continue to plague the Russian ICBM effort until December 1959, when the R 7 was declared an operational weapon. The Americans, meanwhile, made a successful test of their own ICBM, called Atlas, in late 1958.

The ICBM was only part of Korolev's efforts. Korolev had bigger dreams: He wanted to explore space. Under Korolev's direction, Semyorka was became the world's first satellite launcher. On October 4, 1957 it sent the first satellite, Sputnik, into orbit.

Sputnik's bleeping electronic cry, heard by amateur radio operators around the world, announced that the Soviets had scored not only a scientific achievement, but a strategic one. If they could put a satellite in orbit -- and especially the 1,121-pound (2,466-kilogram) Sputnik 2, which carried the first space passenger, a dog, in November 1957 -- then they could loft a nuclear warhead into orbit, where it could threaten any American city. This was already clear after the R 7's test launch in August, but it was only after Sputnik that the American public took the threat seriously.

Spurred in part by the public and media reactions to Sputnik, which bordered on hysteria, U.S. President Dwight Eisenhower stepped up plans for the first U.S. satellite, which had been scheduled for launch as part of the 1958 International Geophysical Year. The first attempt, using a booster called Vanguard, ended in failure on December 6, 1957; the rocket rose only a few feet, then sank back to Earth and exploded. Now hope rested with the U.S. Army's rocket team, headed by Wernher von Braun, who had led the development of the V 2 missile in Nazi Germany. Von Braun's rocket, called Jupiter C, successfully launched Explorer 1 on January 31, 1958. The U.S. had joined the "space race."

But the Soviets held the lead. In January 1959, after several launch failures, they fired a small probe, called Luna 1, past the moon, missing it by about 3,100 miles (5,000 kilometers). Then, just past midnight, Moscow time, on September 14, the Soviets' Luna 2 struck the lunar surface, becoming the first artificial object to reach another celestial body. And in early October, Luna 3 swung around the moon and sent back the first pictures of its hidden face. The Americans, meanwhile, suffered a series of embarrassing failures with their Pioneer spacecraft, which were designed to explore the moon's environment. Most failed to escape Earth orbit; more than one blew up before reaching space. Pioneer 4, launched in March 1959, was able to achieve lunar distance, missing the moon by 37,500 miles (60,500 kilometers).

Even as the two superpowers lobbed robotic spacecraft at the moon, the space race was becoming an even higher-stakes game. In April 1959 seven pilots were selected by the newly created National Aeronautics and Space Administration (NASA) as astronauts for Project Mercury -- the U.S. effort to put a man in orbit. The Soviets, meanwhile, were training their own crop of space fliers, called cosmonauts, who also hoped to be the first into space. In the coming decade, astronauts and cosmonauts would set their sights on historic journeys in space -- not only into Earth orbit, but to the moon.