MOSCOW -- Anxiety is high for this weekend's return of three international space station residents who will be making the first spacecraft landing since the Columbia disaster and NASA's first touchdown on foreign soil.
"I think we are all going to be paying a little bit more attention to landing operations," said Dr. Terry Taddeo, a NASA flight surgeon who will monitor the event from Houston.
With the space shuttle fleet grounded indefinitely, the two American astronauts and one Russian cosmonaut will barrel back to Earth on Sunday in a Soyuz capsule that is a throwback to the Mercury, Gemini and Apollo days.
Instead of splashing into the ocean as in NASA's early days, the capsule will parachute into Kazakhstan. Instead of rolling to a gentle stop on a Florida runway surrounded by swamps and alligators, the capsule will thump down in a remote steppe populated by camels.
Astronauts Kenneth Bowersox and Donald Pettit consider it the experience of a lifetime to cap a stretched, five-month mission. There is no extraordinary angst, Pettit assured reporters this week. Cosmonaut Nikolai Budarin has already been through it twice before.
But in everyone's minds is the fact that the last time humans descended through the atmosphere from orbit, the spaceship broke into tens of thousands of pieces and all seven on board died.
Micki Pettit, the astronaut's wife, admits to being more nervous now because of Columbia.
"Everybody's a little bit more aware of the descent now," she said from her home in Houston, before leaving for Moscow with the couple's 2 1/2-year-old twin sons. "The Soyuz, though, I've heard, is a good, old, reliable workhorse and it's actually got less to go wrong with it than a shuttle would.
"It's going to be a hell of a ride, though. But yeah," she said, pausing, "I'm sure I'll be happy when their feet are on the ground."
To protect against the scorching temperatures of re-entry that penetrated Columbia's damaged left wing and led to the shuttle's destruction over Texas on its way home Feb. 1, Russia's smaller, wingless, bell-shaped capsule has a thick, tough heat shield on the base, similar to NASA's early spacecraft.
It is essentially a ballistic entry, said NASA's space station program manager, Bill Gerstenmaier, and, if all goes well, almost entirely automated. It is a much rougher ride than the shuttle, with crews briefly experiencing up to seven times the force of Earth's gravity, compared to just a few times the force of gravity on the shuttle.
The Soyuz heat shield will pop off shortly before touchdown to expose six small braking rockets that will fire two seconds before impact to soften the blow. Then a convoy of helicopters filled with Russian and American doctors and space officials will descend on the craft to pop the hatch, pull out the spacemen, and examine and congratulate them.
NASA astronauts have not experienced anything like this since 1975 -- and will have to get used to it until shuttles are flying again. Bowersox, the space station's commander, and his crew were supposed to fly back on Atlantis in mid-March, the same shuttle meant to deliver their replacements.
But following the Columbia catastrophe, the replacement crew's flight was bumped onto a Soyuz and into April, and went from three men to two to conserve water and other station supplies. These two -- American Edward Lu and Russian Yuri Malenchenko, who docked at the space station Monday -- will return in their Soyuz this fall.
The only American to land in a Soyuz is California millionaire Dennis Tito, who bought his way into space and back two years ago.
At a space industry conference in Cape Canaveral, Fla., on Wednesday, Tito recalled it was "a pretty wild ride," even by Soyuz standards. Bad data resulted in a steeper than usual return path.
"You're like a meteor coming through the atmosphere, little pieces of heat shield breaking off, flying by your window," Tito said. "Holding on for dear life, hoping that the thing isn't going to break up because at this point there's nothing you can do."
Tito was merely a passenger, while Bowersox -- a former test pilot and shuttle commander -- will serve as flight engineer and help Budarin with the undocking and landing. He could fly the Soyuz himself, if he had to.
His mother has faith in her son's abilities.
"I don't know if I'm crazy or what, but I really don't worry about him," said Jean Bowersox in Bedford, Ind. "I know that Kenny's a Christian and if anything should happen, he's going to be with the Lord. He's doing what he wants to do."
The Soyuz that will bring the crew home -- a space station lifeboat for the past six months-- is a new, roomier model still unproven in re-entry.
Besides offering more leg room, the new capsule has an updated computerized cockpit and extra braking rockets to make for a softer, safer landing. Its first test was the flight last fall to the space station.
In 42 years of manned Russian spaceflight, two missions have ended in tragedy, both during Soyuz re-entries: One cosmonaut was killed in 1967 when the parachute systems failed at the end of a troubled mission. Three died in 1971 when a leak siphoned out all their air.
No matter what the vehicle, "re-entry's a tough environment. I think the Columbia maybe brought that more home than we were thinking about," Gerstenmaier said.
"In the past, you worry about the launch and you don't worry so much about coming home," Taddeo said.
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