GREENBELT -- When astronauts arrive home from a mission in space, television cameras show them nimbly walking down the steps from shuttle to runway, looking confident with big smiles on their faces.
Then they walk along a line of official welcomers, shaking hands and looking hearty.
What the public doesn't see is what the astronauts looked like an hour or two earlier -- a bunch of drunks.
Ronald A. Parise, a Maryland astronaut who was on the crew of the space shuttle Columbia for the nine-day Astro-1 mission in December, shared his experiences yesterday with about 60 adults and children at the Goddard Space Flight Center.
His description of the difficulties faced by returning astronauts was prompted by a child's question about what they do after landing.
"You sit there and try to stand up," Mr. Parise answered. "You get unstrapped and find you can't stand up. It takes a while to be able to put weight on your legs again."
Mr. Parise said that once the crew members achieve the upright position, they weave around a lot. It's difficult, after spending nine days standing on the ceiling, floating in sleeping bags and flying around in the cabin, to remember where the floor is.
"You find out once you stand up. You can't keep your balance," the astronaut said. "You feel like you're going to fall down."
Finally, when the hatch opens and the moment arrives for the astronauts to emerge before a waiting public, they are secretly hoping they won't fall down the steps and land flat on their faces, he confided.
There were other surprises in space noted by Mr. Parise -- effects on body and mind.
Sleeping, for example, proved difficult in a weightless environment. Mr. Parise said he managed to get four hours of sleep daily -- or was it nightly? -- while bobbing up and down inside a harnessed sleeping bag.
"I got almost 2 inches taller," Mr. Parise said, explaining that his spine relaxed due to weightlessness to produce the temporary change in his physique.
And his weight dropped by about 10 pounds -- all water.
"You pee a lot," he said. "There's always a line in the bathroom the first day or two in space."
Flight doctors counseled the crew to drink a lot during the flight to replenish lost fluid so that they wouldn't faint after landing. "Anytime you're not doing anything else, you should be drinking," he said of the doctors' advice.
It is in many ways a different world, being in space.
"Your brain is getting conflicting messages," the astronaut said, describing how fluid in the inner ear that plays a part in perceiving balance is just sploshing around in an environment beyond gravity. While the eyes may provide reassuring clues about one's spatial relationships on Earth, they send crazy messages when the body is floating, and comforting ideas like up and down lose their meaning.
A space ride is fun and constantly exciting, according to Mr. Parise -- but he cautioned that it is also surreal and at times physically uncomfortable.
But the discomfort is minor compared to the thrills, he said. Imagine seeing a sunset or a sunrise every 45 minutes, or looking out the window and seeing the lights of Miami, Tampa, Atlanta, Washington and Baltimore -- all at the same time.
The mission of Astro-1 was to get detailed information through ultraviolet telescopes and other instruments on the chemistry, temperature and structure of stars and galaxies. Now back on Earth at Goddard, Mr. Parise, an astronomer, and other scientists are still analyzing mission data.
And he is looking forward to a return trip out there in two or three years in the crew of Astro-2.