After crashing the space shuttle twice in a row, Bathsheba Luna just shrugged.

"It's very confusing," she said, ducking out of the simulator that allows visitors at the Museum of Flight to try their hand at piloting the massive craft. "I think I pointed it downward too much."

Luna, a visitor from Honolulu, was among a throng of space fans who turned out for Sunday's one-day preview of the space-shuttle exhibit that will have its grand opening in November.

The other big draw was more than a dozen former Soviet cosmonauts, NASA mission controllers and astronauts — including Buzz Aldrin, who along with Neil Armstrong left the first human footprints on the moon.

"He's why I'm here," said Jerry Allen, of Newcastle, who was snapping pictures of the 122-foot-long Full Fuselage Trainer that's the star of the exhibit. Built in 1979, the mock-up was used to prepare crews for every shuttle mission.

"I'm impressed," Allen said. "It's bigger than I thought it would be."

Aldrin, 82, and the five other NASA veterans who made up the day's first panel got a standing ovation as they filed onto the dais. The Apollo 11 astronaut, who followed Armstrong onto the lunar surface on July 20, 1969, read from the final chapter of his upcoming book, urging America to reinvigorate its space program.

"A unified space vision can ignite a new wave of participation and support in the U.S. and elsewhere," he said.

Aldrin also paid tribute to Armstrong, who died last month. "Neil did not see Apollo 11 as an ending," Aldrin said. "As he once observed, there are still places to go beyond belief."

A strong proponent of a manned mission to Mars, Aldrin suggested using Moses Lake, in Eastern Washington, as a training ground. With a 13,500-foot runway, the airport there was once considered as a spaceport for a next-generation shuttle. Astronauts could simulate building and mining on Mars there, he said.

The audience laughed and clapped as the gray-haired men described experiences shared only by a tiny corps of space travelers.

For astronaut Jack Lousma, nothing was better than a spacewalk. Lousma piloted the shuttle in 1982 and spent nearly two months onboard Skylab, the first U.S. space station, in 1973.

From inside the vessels, it was hard to get a good look at the Earth, Lousma said. But outside, the view was crystal clear and the silence profound. "It was like a magic carpet," he said. "You just wanted to stay out there forever."

In fact, Lousma admitted to doing everything he could to extend his time outside. One of his walks stretched over six hours.

Skylab 4 astronaut Gerald Carr described one restless night when he slipped out of his sleeping bag, floated up to the command module and strapped himself in the seat. He watched the changing Earthscape below as the craft zoomed by overhead at six miles a second. He picked out Tokyo Bay, the Aleutian Islands with their volcanic cones poking through the clouds, San Francisco Bay and Los Angeles shimmering in the night "like a big velvet bowl full of diamonds and pearls."

National boundaries are invisible from space, Carr pointed out. "We need to look within ourselves and take care of our planet."

The view into deep space was equally captivating, Carr said. "You're looking at a billion more stars that you can't see from down here," he said. Picking out familiar constellations to navigate by is tough against the glittering backdrop.

In zero-gravity, the men slept vertically, their sleeping bags hanging from the wall. One astronaut, who liked a breeze, preferred to sleep head down to be closer to the air vents, Carr said. Velcro straps kept the astronauts' heads from lolling around all night.

The space men didn't address the No. 1 question astronauts are asked: How do you go to the bathroom?

But the Museum of Flight exhibit addresses the issue unflinchingly with a full-scale model of the shuttle's Waste Collection System. Negative air flow sucks the waste from the astronaut's body. Solids are stashed for return to Earth. Liquids are periodically jettisoned into space.

Geri Culwell, of SeaTac, was marveling at the seat belt and foot restraints that keep the astronauts ensconced in the saddle of the sanitation system. "They have it all figured out," she said.

Which is a good thing, added her friend, Martin Owings. "It could get messy unless you use it properly."

Sandi Doughton: 206-464-2491 or sdoughton@seattletimes.com