By Bob McDonald, Quirks & Quarks

Who could have imagined, back on April 12, 1961 - as America watched, stunned, as cosmonaut Yuri Gagarin became the first human to travel in space - that 50 years later, U.S. astronauts would be hitching rides on Russian rockets?

Gagarin's flight lasted only 108 minutes, but its symbolism will last forever. It was the first jump off the mark in the superpower race into space, a race that was supposed to lead to the next great era of human exploration of new worlds. The United States was quick to respond to Gagarin's accomplishment, and in an astounding feat of catch-up, won the race to the moon only eight years later.

At that rate, it looked like humans would be on Mars in another decade, and according to science fiction author Arthur C. Clarke, out to Jupiter by 2001. But that hasn't happened.

Half a century later, humans can travel no farther that 400 kilometres above the planet; no one has been to the moon since 1972; and the once mighty American space program is entering a state of limbo, in which the space shuttle will retire and astronauts have no way of getting to space, other than by paying for rides on Russian rockets that have not changed much since Gagarin's flight. In fact, the latest launch used the same launch pad.

What a turnaround.

One reason we haven't gone anywhere in space is because Gagarin's flight was not really about him; it was about the rocket that carried him aloft. His flight was a demonstration of a powerful new weapon technology being developed on both sides of the Atlantic called the intercontinental ballistic missile, or ICBM, a rocket capable of delivering a nuclear weapon anywhere in the world.

It was that cold war technology that drove the early space program in both the Soviet Union and the United States, not the scientific exploration of the cosmos. Early American astronauts were flying into space on ICBMs as well. Space was the ultimate military high ground, a place to demonstrate technological superiority.

The goal of reaching the moon was clear: build the world's biggest rocket and get there first. But once that goal was accomplished, with footprints and a flag on the moon in 1969, the demonstration was complete, so the military motivation for going back vanished.

Following the moon landings, the Soviet space program abandoned its large moon rocket, the N-1, mostly because it had a bad habit of exploding during launch. So they returned to a slightly larger version of the Soyuz, the tried-and-true rocket that carried Gagarin into orbit. In fact, before his untimely death in a plane crash in 1968, Gagarin himself was training to fly in a Soyuz capsule of the same design used by cosmonauts today.

In other words, the former Soviet, now Russian, space program has followed the old adage, "If it ain't broke, don't fix it." By sticking to proven technology, they have followed a steady step-by-step progression that led to multiple small Salut Space Stations, a larger station called Mir and being able to provide the first central core unit to the International Space Station.

Those cold war-era rockets are still the cheapest and most reliable way to send humans into space. They have even flown tourists on holidays to the Space Station.

The Americans re-invented themselves with the space shuttles, which have proven to be both enormously expensive and dangerous - of the five that were built, two were destroyed in flight, taking 14 lives. But U.S. astronauts now find themselves in the somewhat embarrassing situation of having to buy seats on the Russian craft, so they can get to the space station after the shuttles are retired later this year.

Talk about a tortoise-and-hare situation: the slow and steady approach has worked in the long run for the Russians. A moon mission is not officially on the agenda, but some in the space community believe that with a few more modifications to the Soyuz - and a partnership the Chinese space program - they could land humans on the moon in the next decade.

If they do it in 2019, that would be the 50th anniversary of the first moon landing by the Americans. So while the Russians lost the first sprint to the moon in the 1960s, they continue to maintain a steady presence, while the Chinese press ahead. There is a very good chance that the next two flags to be planted there will be red.

If you want to hear the extraordinary story of Yuri Gagarin, first human in space, tune in to Quirks and Quarks this week, where we'll speak to his biographer.