SPACE CENTER, Houston The story goes something like this:

A job candidate from one of the most feared military commando forces in the world sat before NASAs astronaut selection board back in the 1980s, and the panel primarily made up of veteran space fliers asked him a standard interview question.

[inset]

"What is it that you do better than anyone else in the world?"

Bill Shepherds purported response:

"I kill people with a knife."

Its a story that seems fitting for a former Navy SEAL whose training class co-opted its motto from a Federal Express ad slogan: "If it absolutely, positively has to be destroyed overnight"

~

The strong influence of his father the late George R. Shepherd and an ingrained love of the sea propelled him to the U.S. Naval Academy, where he earned a bachelors of science degree in aerospace engineering in 1971.

"I guess I was one of those kids that, you know, you kind of take a direction when youre really young, and sometimes you stay with it, sometimes you leave it and go back to it, but ever since I was really small, I always liked boats [and] being around the water," he said.

"And I always thought that the Navy would be a pretty cool thing to do, and I kind of left that idea for awhile, but as I finished up high school, I decided thats what I was going to do, so thats how I went that way."

Shepherd wanted to follow his fathers footsteps and aimed to become a naval aviator, but he couldnt pass the requisite eye exam, so he set out to become a diver instead.

Expedition One crew members stand before a Russian official reporting their readiness for launch to the International Space Station on October 31, 2000.

That led to a tour of duty with a U.S. Navy Underwater Demolition Team. Then Shepherd served on two Navy SEAL squads that carried out clandestine missions he could tell you about, but then, of course, hed have to kill you.

The classified nature of Shepherds work continued even after he joined ranks with NASA.

His first shuttle flight in 1988 was a top-secret mission during which an advanced Pentagon radar reconnaissance satellite reportedly was delivered to low Earth orbit.

Shepherd also flew on a controversial shuttle mission to dispatch a plutonium-powered spacecraft to study the Sun in 1990. Two years later, he flew on a science mission that aimed to map Earth by bouncing laser beams off the planets surface.

With three shuttle flights under his belt, Shepherd was called upon in 1993 to join the ranks of NASA management, and for the next three years, he served in the agencys space station program office.

He was deputy director of the program office when the Clinton administration ordered a sweeping redesign that ultimately led to the inclusion of the Russians in the $60 billion International Space Station construction project.

~

The latest and seemingly longest chapter of Shepherds career dates back to November 1995, when the U.S. Navy captain gave up his desk job for a chance to serve on the first full-time crew of the international outpost.

The mission at that time was supposed to launch in 1997, but a long and frustrating series of Russian political, financial and rocket problems conspired to delay the flight again and again.

Consequently, the former SEAL has spent five years training for a four-month flight an endeavor that has made crawling through malarial swamps seem like a stroll through the park.

Shepherd is helped into his suit at the Neutral Buoyancy Tank Facility in Star City.

"I can tell you personally I had been through a lot of things even before NASA that were very difficult, and this is one of the hardest things Ive had to do," he said.

And the ordeal has been no easier on his mother, Barbara Shepherd of Bethesda, Maryland, or his wife, the former Beth Stringham of Houston, a physical therapist who works with astronauts both before and after extended stays in space.

As fate would have it, Shepherd and his wife got married right about the time that the veteran astronaut was named to the so-called Expedition One crew.

The couple, as a result, has had to endure lengthy separations as the would-be station commander commuted between Houston and Star City, Russia, home of the Gagarin Cosmonaut Training Center outside Moscow.

"Its been really tough on my wife," Shepherd said. "This is about all shes known a lot of travel, and me being on the road a lot, away from her. It has not been an easy job."

Another lengthy separation is in the offing. This one will last until shuttle Discovery flies up to the station and then returns Shepherd and his two cosmonaut colleagues to a Kennedy Space Center runway on February 26.

So whats he looking forward to most about his latest mission?

"Having a successful 'wheels stop in Florida," Shepherd said, "and being able to look back at the mission, saying we did our job well."

Time will tell.