Commander Dominic Gorie thought his third shuttle flight more than six years ago would be his last -- until he got the call to head up this one.
"To get a fourth flight was a truly a surprise, a pleasant surprise for me, but a challenge certainly for the family. My kids were actually quite supportive," although nervous, he said. His daughter is 20 and his son 18.
"It was more of a challenge to talk my wife into it, but she knew -- and knows -- why I do what I do and why NASA does what we do. But it is very, very tough, especially having lived through the loss of Columbia and the friends that we had on that flight."
Gorie, 50, a retired Navy captain, flew 38 combat missions in Operation Desert Storm in 1991 and was selected as an astronaut three years later.
The last time Gorie rocketed into space, it was the first shuttle launch after the Sept. 11, 2001, terrorist attacks. His words from the cockpit right before the high-security liftoff -- "Let freedom roar" -- stirred emotions in launch control and elsewhere.
Gorie was born in Lake Charles, La., and grew up in Miami.
Pilot Gregory Johnson comes from a musical family -- his late father was an Air Force band leader, and his brother is a musician, composer and church choir director in Dayton, Ohio, where they all grew up.
Although playing the trumpet and piano didn't make him more qualified to be an astronaut, "the lessons I learned in discipline and teamwork in making music in high school and college, by the way, have been serving me well over the last couple decades."
Johnson, 45, an Air Force colonel, flew 34 combat missions during Operation Desert Storm in 1991 and went on to test pilot school. NASA picked him as an astronaut in 1998.
This will be his first spaceflight.
"I won the lottery on this flight," he said. "It's got the mission, it's got the crew, it's got everything. I wish my first mission came a little sooner. It's been an exercise of patience, but I'm really lucky, just amazingly lucky to be on this flight."
Johnson is married with two sons, 14 and 13, and a 10-year-old daughter.
The mission's lead spacewalker, Richard Linnehan, is a veterinarian-turned-astronaut who visited the Hubble Space Telescope on his last flight.
Working on Hubble was like surgery, he said. Hooking up a new room for the space station and assembling a two-armed space station robot is more like longshoreman work, he said, and in ways it's harder.
Linnehan, 50, will be making his fourth and final space shuttle flight, and will perform three spacewalks on the mission.
He was chief clinical veterinarian for the Navy's marine mammal program in San Diego when NASA picked him as an astronaut in 1992. With doctors and scientists being picked to fly in space, he figured, "there's no reason why they couldn't use a veterinarian."
He plans to devote more time to marine mammal conservation, taking advantage of Earth-observing satellites, once this mission is over.
Linnehan grew up in Hudson and Pelham, N.H. He is single.
Navy Capt. Michael Foreman wanted to be an astronaut ever since he was 8 years old. It took years -- and eight applications -- to achieve his goal.
The 50-year-old Foreman grew up in Wadsworth, Ohio, in John Glenn's home state.
"I started to follow the space program and read some books about the early astronauts and just decided that's what I wanted to do," he said.
He's been an astronaut for 10 years and is about to make his first trip into space. He'll perform three spacewalks.
"The challenges are really out there" on this flight, he said. "I mean, this is setting up the bar pretty high."
He is carrying up a stuffed giraffe for Texas Children's Hospital in Houston, where his wife works. They have two sons, 23 and 19, and a 15-year-old daughter.
Robert Behnken is waiting to set a date -- a wedding date -- until the mission is over and he's safely back on Earth. His fiancee also works for NASA.
He's taking into space their wedding rings, as well as the wedding rings of friends.
Behnken, an Air Force major with a doctorate in mechanical engineering, became an astronaut in 2000. At age 37, he's one of NASA's younger astronauts and plans to stick around until the next-generation spaceship is flying.
"Just like any other kid, I wanted to be an astronaut and a fireman and a rock star and all those things when I was a boy," he said. He liked science and math, and that led him to engineering and the Air Force.
Behnken will perform three spacewalks on his first mission, including one to test a caulking gun and high-tech goo for repairing damaged shuttle tiles. His partner will actually squeeze the trigger; Behnken will be floating nearby with a garbage bag to catch any excess foaming goo.
He is from St. Ann, Mo.
Garrett Reisman will be left at the international space station and return to Earth aboard Discovery in June.
While Endeavour is still at the space station, Reisman, 40, will perform one spacewalk, the first of the mission to begin assembling a two-armed robot and help install a Japanese storage compartment. This will be his first spaceflight since becoming an astronaut 10 years ago.
"If you asked me what I was going to be when I grew up, I probably would have told you a doctor maybe or an engineer," said Reisman, who has a doctorate in mechanical engineering. "But I just never thought it was within the realm of possibility that I could actually have the opportunity I'm going to have."
He watched his family's old movie version of the Apollo 11 moon landing so often, while growing up in Parsippany, N.J., that he had to keep splicing the film together with tape.
Reisman is married to an oceanographer.
"We kind of made an agreement that we would divide things up. I'll take sea level and above, and she'll take sea level and below," he said. "We violated that agreement, though. I was down there on Neemo (the underwater habitat) for two weeks, and she got her pilot's license."
Japanese astronaut Takao Doi considers it an honor to be the one who will hook up Japan's new space station compartment.
It is the first part of Japan's Kibo lab that is so big that three shuttle flights will be needed to hoist everything.
"This is the first time that Japan will have its own manned facility in space, so I am very honored to be part of this program. Especially, I am very excited that I am the one who is going to operate the shuttle robotic arm and install this first module of Kibo to the space station," he said.
Doi, 53, has two doctorates, one in aerospace engineering from the University of Tokyo and one in astronomy from Rice University in Houston. He was selected by the Japanese Space Agency as an astronaut in 1985 and flew aboard a space shuttle in 1997.
Doi, who is married, is taking up Japanese rice and noodles, as well as chopsticks for all 10 people who will be in space. He also will test a paper boomerang at the international space station to see if it comes back to him in weightlessness. He's practiced throwing boomerangs on Earth and says "it's not so difficult."
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