London — The United States is making an all-out effort to persuade its allies to bnjoin it in planning an $8 billion manned space station for the 1990s. During a 10-day tour, NASA administrator James Beggs offered joint ownership of the station to West Europe and Japan. NASA wants to know by early 1985 which nations plan to join the program. Participating countries would have to put up as much as $2 billion beyond NASA's share.
Speaking in London last week, Mr. Beggs stressed that the space station would be improved by foreign participation. ''America has no monopoly on brains,'' he said.
President Reagan outlined plans for the station in January. According to NASA officials, it will be both a laboratory and a staging post for space probes.
Mr. Reagan singled out Britain, France, West Germany, Italy, Canada, and Japan as possible partners in the project. Mr. Beggs is traveling to all these nations (except Canada).
NASA officials stress the US is open on the design of the space base. They are approaching it in much the same way a builder designs a condominium to be owned by several individuals.
If possible, NASA wants the design finalized by interested parties well before building work starts. But if other countries show only lukewarm interest, the US will probably go ahead with construction of a central core of the station that contains essential life support systems, basic laboratory equipment, and so on. Other countries could add their own modules to this core at a later stage.
In an interview, Mr. Beggs said the US would not object to non-US vehicles docking with the station. And he said scientists would not necessarily be tied to the parts of the base paid for by their governments - although some commercially sensitive parts would be out of bounds.
Mr. Beggs appeared to be responding to fears in Europe that the US might strike a hard bargain. West European nations are annoyed that NASA requires them to pay a fee for use of Spacelab, which was built by the European Space Agency. In the future, European officials say they must have free use of technology developed by Europe.