London — Western Europe is responding cautiously to United States' overtures on involving other countries in its plans for an orbiting space base for the 1990s. The nations are concerned that a joint effort might mean Western Europe loses out by playing second fiddle to the Americans. The countries also need convincing that a space station would provide benefits to justify its costs.
Officials at the National Aeronautics and Space Administration are formally inviting Western Europe, together with Canada and Japan, to collaborate on the $ 8 billion space station, plans for which were unveiled by President Reagan in his State of the Union address last month.
The United States has unofficially sounded out these countries over the past two years. Now James Beggs, NASA's administrator, is to travel to the nations to discuss in detail how they may get involved.
In Western Europe, West Germany and Italy have shown the most positive attitude. They have cooperated for more than a year on a study on how Europe could build a space station.
Called Columbus, the project envisages that Western Europe adapts space hardware already built under the Spacelab program.
Spacelab is the world's first reusable orbiting laboratory, built by the 11 -nation European Space Agency (ESA) for $750 million. Parts of the hardware, which made its maiden flight inside the cargo bay of a space shuttle last November, could be adapted to form modules of the proposed space station.
For example, Spacelab's dustbin-shaped experiment quarters, which contain room for several people, could form accommodation units or laboratory space for the US's orbiting base.
Columbus's title has been chosen to appeal to the more visionary among government planners. ''Europe discovered America in 1492,'' explained an official in West Germany's Ministry of Research and Technology. ''We think 1992 would be a good year for Europe to establish itself in space.''
But West Germany is adamant that Europe should involve itself in the US program only if the terms are right. If these are less than favorable, according to a civil servant, then Europe should build its own space station as a way of ensuring independence for the continent's space technologists.
Costs for the Columbus project would vary depending on what is implemented. To construct an autonomous module that could be ''plugged into'' the core of the US space station would cost $1 billion to $2 billion, West German space planners say.
West Germany is particularly keen to develop Spacelab further because it paid more than half the bill to develop the orbiting laboratory. It is therefore keen to amortize its investment.
The country is also concerned that Europe present a joint viewpoint on the station. Heinz Riesenhuber, West Germany's minister for research and technology, wants to lead a delegation of European government officials and space engineers to the US. If the other countries agree, the visit could go ahead in March or April.
Space engineers in Western Europe are concerned that, in any venture with the Americans, the US would gain control over European technology. A joint venture could repeat the problems that the Europeans suffered over Spacelab. Under a 1973 agreement, Europe had to hand over the hardware after the maiden flight.
So despite the cash spent on developing Spacelab, any European country will have to pay about $150 million to rent Spacelab from the US on further flights, much of this represented in fees to NASA for using the shuttle.
Jacques Collet, a planning official at ESA, said: ''Whatever form the cooperation (over the space station) takes, Europe will have to play a part not just in the development but in the utilization stage. We believe that the position is completely different compared to the start of the Spacelab program. Europe has demonstrated it can build large space stations and the US should look upon us more as equal partners.''
Western Europe has still to be won over to the view that the space station will provide benefits.
An official in Britain's Department of Trade and Industry said Britain welcomed the announcement by Mr. Reagan and will participate in talks over collaboration.
But the United Kingdom will get involved - perhaps by paying for some of the hardware that West European nations develop in a joint approach - only if the space station produces ''spin offs'' in technologies for use on earth.
''The watchword must be 'space for profit,' '' the official said.
Prof. Heinz Wolff, chairman of ESA's advisory committee on microgravity experiments, said he doubted whether a manned space station can produce better scientific results than unmanned platforms, which are much cheaper. Professor Wolff is head of the bioengineering institute at Brunel University near London.
Prof. Ken Pounds, another leading U.K. space scientist, noted that the announcement by Mr. Reagan was made in an election year. Professor Pounds is in the space physics department at Leicester University.
Another worry for Europe is the issue of technological exports to Europe, on the grounds that secrets might leak out to the Soviet Union. Such an atmosphere is not conducive to a joint project between the US and Western Europe which would involve pioneering advances in technology, according to space engineers in Europe.