The middle-aged Soviet cosmonaut, to no one's surprise, advocated better U.S.-Soviet relations. He had fond memories of his 1975 joint mission with the American astronauts and high hopes for future joint voyages, perhaps even a trip to Mars, he said on the 10th anniversary of the Apollo-Soyuz mission at a House reception last night..

"The Soyuz-Apollo was a symbol of a general warming-up of the general political climate in the world and in Soviet-U.S. relations. I hope that we are capable of repeating this kind of a program," said the former Soyuz commander, Gen. Maj. Aleksey Leonov, 51. He spoke through an interpreter to the astronauts, cosmonauts and about 100 others at the Rayburn House Office Building. During their two-day joint activities that July, the astronauts and the cosmonauts docked their spacecrafts, ate a meal together, exchanged gifts and performed several joint experiments.

Former U.S. astronaut Donald "Deke" Slayton said the 10th anniversary celebration was contributing to U.S.-Soviet dialogue. "I think we're still getting some benefits out of it the mission . I mean, the Russians are here talking to us and we're talking to them."

And the talking drew attention to space projects, with a reception, two press conferences and a space symposium Tuesday and Wednesday. "The most important thing we do in this program is to discuss the potential opportunities," said James Beggs, administrator of the National Aeronautics and Space Administration. "It is a good way of getting ideas out to the public."

There was talk of sending a two-year manned mission to Mars, 35 million miles away, sometime in the next few decades. He suggested that such a mission might explore Mars' geography for clues to the history of Mars, the sun and the universe.

Words on when a manned mission to Mars would take place were tantalizingly vague. "We've come to the point where we can consider this thing as a practical matter. I think you are going to witness a trip to Mars sometime in the future," said former cosmonaut Valeriy Kubasov, 50, who now researches space technology.

Rep. Robert Walker (R-Pa.), who is on the House subcommittee on space, said such a mission would be so expensive that several nations might have to shoulder the costs. "The whole business of a long mission lends itself to a joint effort more than anything else."

A Mars voyage is not the United States' first priority, however, said Walker. "With the kind of budgetary restraints that we're under with the domestic space program, the first step is building a space station."

Despite funding problems, Walker has high hopes for the space program. "I expect, within the next 25 years, to be able to stay at a space hotel," said Walker.

The astronauts may have preferred being in space to being on the Hill. "Given the choice, we'd all be up there today flying, rather than down here," said Slayton, 61, gesturing to former Apollo commander Thomas Stafford, 54, and crew member Vance Brand, also 54.

"I'm willing to go to Mars or anywhere else," he added. "Of course, I'd be gone a long time. I'd take my lunch."