Leading Article: Place no bounds on our quest for knowledge

THE ACTION in one of the most memorable episodes of Star Trek took place on a planet populated by two tribes of humans called Yangs and Coms. A transparent allegory of the space race between America and Russia, the planet had been colonised by the Yanks and the Communists and then forgotten, stalled in time. The planet's inhabitants, too, had forgotten why they were there, retaining only distant, distorted folk memories of the 20th-century Cold War which sent them there. The Yangs had their sacred word, freedom, the meaning of which they had lost; and the Coms had theirs, peace.

The Cold War may be over, but symbolic words and national pride retain their importance in space. The Russian space station, Mir (Russian for "peace" and also "world"), is now to be replaced by a giant international space station - the extra-terrestrial foundation stone was launched into orbit yesterday. The new space station will be the first artificial "star", as bright an object in the night sky as one of the planets - if we can see it through the orange murk of our streetlights.

It is, as ever, a telling symbol of the state of politics on the Earth's surface, 219 miles below. It is a joint venture, an example of post-Cold War co-operation, although on inevitably unbalanced terms. The United States is putting up almost all of the money, despite understandable Congressional reluctance to commit the $60bn (pounds 37bn) estimated for the eight-year project.

The Russians are providing most of the rocket power: after all, there are plenty of ballistic missiles gathering dust in mothballed silos all over the former USSR. Meanwhile, the Canadians, Japanese and Europeans have a token role, and might be allowed to select an astronaut or three.

But who needs it? The space station has already been labelled the orbiting white elephant, and NASA is desperately trying to think up things for it to do. Already the US space programme is in such trouble with its paymasters in Congress that it was reduced to last month's publicity stunt of putting one - Senator John Glenn - into space. There is no real scientific justification for the space station, just as there was none for putting Senator Glenn into orbit - forget all that tosh about experiments on the effects of weightlessness on the ageing process.

This was effectively conceded by NASA when it developed its twin-track strategy in response to budget cuts in the Eighties. It declared it would focus on unmanned and relatively cheap probes into distant space on the one hand, and what it called its "mission to Planet Earth" on the other. This meant space exploration which would add to our understanding of our own planet, and produce clear benefits for those living on it. The international space station should come into this second category, but it is hard to find an independent scientist to make that case.

Which raises a wider question. Apart from the invention of Teflon, what has the exploration of space ever done for us? As it happens, Teflon was not a product of the Apollo Moon mission. It was invented in 1938 - it was simply made famous by its use in space suits. The mission did have beneficial, if less tangible, spin-offs, by accelerating the development of computers and huge public-sector project management, but, viewed through the narrow prism of a cost-benefit calculus, space projects are an inefficient way to advance technology. As one scientist pointed out: "When Kennedy made the decision to go to the Moon, these considerations were nowhere in his mind. He was willing to commit the resources for a political demonstration of the superiority of a democratic system." It was a matter of Yangs versus Coms.

In the end, though, the justification for exploring space is humanity's sense of wonder. There can be no doubt that landing men on the Moon captured the imagination of a generation of young people, many of whom were inspired to study science. And it is only by better understanding our place in the universe that human rationalism can defeat the still-fashionable appeal of cults, mysticism and the supernatural. The new space station may not be the best or the wisest spending of America's money, but scientific discovery is driven by stepping into the unknown and seeing what happens, as well as by immediate economic advantage. There should be no bounds placed on humanity's quest for knowledge.