He is supposed to spend the next four months aboard the rickety, accident-prone Russian space station Mir.
If Wolf moves into Mir, he will become the sixth American to live on the 11-year-old orbiting station.
But all week, top U.S. officials were debating whether to let another American take such chances.
A fire, a collision and a mess of malfunctions have tarnished Mir's reputation in recent months. The problems have led many American officials to conclude that sending another astronaut into space is too dangerous. NASA administrator Daniel Goldin, however, was expected to have the last word.
Wolf, a 41-year-old doctor and engineer, apparently has no fears about living aboard the craft.
"I'm not playing Russian roulette or spinning dice to see how many times I can do it before something bad happens," the never-married Indianapolis native told the Associate d Press.
His mother, Dottie Wolf, wasn't as sure.
"I wouldn't mind if they canceled the whole thing," she told the AP.
He has dreamed of becoming an astronaut since his boyhood in a Conservative Jewish home.
"It's kind of a goal since childhood. I watched all the flights, and I remember watching Ed White doing the first space walk when I was 11 years old and that got me particularly interested."
He went on to earn a bachelor's degree in electrical engineering at Purdue University and a medical degree at Indiana University.
In 1983, Wolf joined the medical sciences division at the Johnson Space Center in Houston and worked in medical research. At the center, Wolf was responsible for developing what is called the American Flight Echocardiograph for investigating cardiovascular physiology in microgravity.
In 1990, NASA tapped Wolf to become an astronaut . A year later he qualified for spaceflight.
Wolf was part of another unique flight crew when he traveled aboard a Columbia shuttle flight in the fall of 1993 with a fellow Jewish astronaut, Martin Fettman. That flight, too, was set to go during the High Holy Days, and Wolf took along a shofar as well as a few mezuzot.
On this flight, Wolf will be the only Jewish member of the team. His Judaica supply this time is unknown.
Wolf knew that eventually he might become a Mir crew member.
He spent time last year at the Gagarin Cosmonaut Training Center in Star City in Russia to prepare him and to learn Russian.
But Wolf learned only last month that he would become the next replacement for astronaut Michael Foale.
Wendy Lawrence, a 5-foot-3 astronaut, was disqualified when officials realized she was too small for the Russian space suits.
Despite the numerous troubles the Mir has endured, 5-foot-10 Wolf said the effort is worth it.
"Every minute we spend in the joint program is invaluable to us. We're getting many times our planned return from the joint shuttle-Mir mission…People should be very proud of our space program."