Orbital manoeuvres in the dark

This summer efforts to build the world's first international space station will enter a crucial phase.

In a couple of days' time, on 1 June, a 20-ton scientific module called Spektr (Spectrum) should dock with Russia's Mir space station 250 miles above our heads. It will be the prelude to a period of intense international activity in space, culminating three weeks hence when the American space shuttle Atlantis will dock with Mir. It will be the first such rendezvous in space for 20 years, since the joint Apollo-Soyuz mission in July 1975.

The Shuttle-Mir programme originated at the end of the Cold War. In 1992, Russia and the United States decided to pool their resources and work with Europe, Japan and Canada to construct the world's first international space station. Since the first section of the Alpha station is not due for launch until 1997, the US National Aeronautics and Space Administration (Nasa) and the Russian Space Agency (RSA) decided to gain valuable flight experience through a joint preparatory programme. Nasa agreed to pay the Russians $400m in return for a minimum of seven shuttle dockings with Mir and up to two years of astronaut time on board the ageing Russian craft (Mir was first launched in 1986).

The nomenclature of the space programme itself reflects political preoccupations with the Cold War. When Ronald Reagan first announced that the United States would demonstrate the superiority of the American free-enterprise system over Soviet-style communism by building the space station, it was to be called "Freedom". The Soviet station's name Mir, in contrast, means "Peace". With the ending of the Cold War and the realisation that Reaganomics had not equipped the US to go it alone, the station was internationalised and acquired a less ideological name.

The first stages in the Shuttle-Mir programme were successfully accomplished when Sergei Krikalev became the first cosmonaut to fly on a shuttle, in February 1994, followed in February this year by the first close-approach between a shuttle and Mir. As the shuttle Discovery closed with the Russian station, the cosmonaut Vladimir Titov, on board Discovery, was able to look through a window and wave to his compatriots on Mir, just 33ft away.

In March, it was the turn of the Russians to play host as the astronaut Dr Norman Thagard became the first American to lift off from the Baikonur cosmodrome at the beginning of a record-breaking stay aboard Mir. Since then, unfortunately, the entente cordiale has been severely tested by delays and technical hitches on the Russian side that have forced Nasa managers to draw up a series of new contingency plans.

Last autumn, US medical experiments were held up by Russian customs officials. This delayed the preparation of Spektr and its launch date slipped from February to 11 May. Further slippage followed as the Mir crew ran into difficulties while preparing the space station for the new module's arrival. As a result of Spektr's late arrival, Dr Thagard has spent a frustrating three months waiting for most of his medical experiments to be delivered.

The delay has had a knock-on effect. Under the original plan, the historic link-up between Atlantis and Mir was to have taken place in early June. The shuttle would be used to carry two Russians to Mir, then return Dr Thagard and his two cosmonaut colleagues to Earth after 95 days aloft. With the postponement of the shuttle docking until 24 June at the earliest, the Mir crew will be obliged to wait several weeks longer until their taxi arrives to take them home.

The main cause of these difficulties has been the sheer complexity of the planned orbital manoeuvres. First, in order to clear the way for the link-ups with Spektr and Atlantis, the Mir crew were scheduled to make four spacewalks, to stow one solar panel and transfer another from one end of Mir to the other. With the ageing Mir suffering from a perpetual power shortage, it was not possible simply to disconnect the huge "wings" and throw them away.

The sequence of spacewalks began on 12 May, but the cosmonauts ran into trouble when they tried to retract one of the five-year-old arrays. Five days later, with the aid of a crane mounted on the exterior of Mir, they eventually transferred the panel to the station's rear end. But despite staying outside for almost seven hours and coming close to running out of oxygen, they were unable to reinstall the panel in its new location. Only after a third excursion, on 22 May, was the exercise completed. A fourth spacewalk took place yesterday, and a fifth is planned for 2 June, to complete the preparations for the arrivals of both Spektr and Atlantis.

But this is not the end of the story. During the coming weeks, the crew will have to supervise a complex rearrangement of the four modules that make up Mir. Once Spektr is safely docked, it must be moved to a side slot so that the Kristall module can be relocated at the front. Kristall is the only Mir module equipped to dock with a shuttle.

These operations will be watched with great interest on the other side of the Atlantic. Not all US politicians and space officials are in favour of the Russian connection, and these opponents would be only too ready to criticise the alliance if major problems arise. Congressman Steve Stockman, a member of the House Science Committee, recently commented, "Russian participation ... has intertwined our hopes for station success with Russia's ability to deliver as promised. This should raise some red flags to all [international space] station supporters, regardless of their views of Russian participation." So strong were the doubts of some leading US politicians that the Nasa chief, Dan Goldin, was forced to draw up contingency plans covering the possible withdrawal of Russia from the Alpha project.

Supporters of the pact argue that the project will be completed faster and cheaper with the aid of Russian hardware and expertise. Certainly, until the Russians arrived, there were mountains of paperwork but little practical progress towards building a space station, mainly because US politicians kept moving the goalposts. Half a dozen redesigns and funding cutbacks generated concern at home and abroad about the chances of Alpha ever being completed.

Whatever the outcome, the will and determination of all sides to work together for the common good will come under severe scrutiny. Unless East and West can work together through the trials and tribulations that will face them, the world's first multi-national space station will not be built and placed in orbit by the turn of the century.