A Russian rocket launched the world's third space tourist and two astronauts into orbit Friday, beginning a two-day trip bound for the International Space Station (ISS).

Tucked inside their Soyuz TMA-7 spacecraft, space tourist Gregory Olsen and the twelfth ISS crew lifted off from their Baikonur Cosmodrome launch pad at about 11:55 p.m. EDT (0355 Oct. 1 GMT) after a smooth countdown on the steppes of Kazakhstan.

"The crew is doing well, everything is fine on board," Soyuz commander Valery Tokarev, who also serves as flight engineer for ISS Expedition 12, said from orbit.

Tokarev sat in the center seat of the Soyuz TMA-7 spacecraft and was flanked by Olsen on the right and Expedition 12 commander Bill McArthur, a NASA astronaut, on the left.

"To watch this flawless launch on a beautiful day is just amazing," said Bill Gerstenmaier, NASA's associate administrator for space operations, who attended the launch. "[The crew] will be maintaining the station and they'll have an exciting and very busy increment."

The Expedition 12 crew and Olsen have a two-day orbital chase ahead of them and will conduct a series of three engine burns to raise their orbit to meet the ISS. Docking at the orbital laboratory is currently scheduled to occur at about 1:32 a.m. EDT (0532 GMT) on Oct. 3.

While McArthur and Tokarev are relieving the current crew aboard the ISS - Expedition 11's Sergei Krikalev and John Phillips - Olsen is paying $20 million to visit the orbital laboratory. He is the third fare-paying visitor to the station under a contract brokered with Russia's Federal Space Agency by the Arlington, Virginia-based firm Space Adventures.

"Today marks another triumph in commercial space travel," Space Adventures CEO Eric Anderson said in a statement. "Greg has been committed to this mission since day one."

 Space Adventures also brokered the ISS flights of Dennis Tito in 2001 and Mark Shuttleworth in 2002.

"It's a very challenging program, but I enjoyed it," Olsen said of his training during a prelaunch press briefing. "It was really one of the highlights of my life."

Olsen's road to space has not been problem-free. After initially announcing his intention to fly to the ISS in March 2004 and beginning flight training one month later, Olsen cut short his preparations when Russian space officials reported that he had an undisclosed medical condition that prevented him from continuing.

That medical condition was later resolved and Olsen resumed flight training on May 14, 2005.

"This has been two years of very hard work for me," Olsen said at the briefing. "I don't think anyone with six months of preparation would be able to fly this mission, it takes years of practice."

Another glitch concerned Olsen's science plans for his time onboard the space station.

He had hoped to tote an infrared camera built by his Princeton, New Jersey-based firm Sensors Unlimited, Inc. to the ISS, but was ultimately unable take it aboard Soyuz. Instead, he will perform three medical experiments for the European Space Agency (ESA) during his eight days aboard the station. Olsen, who prefers the term "spaceflight participant" to "space tourist," will also speak to students from his orbital perch and observe the Earth.

"Greg has already outgrown the title of space tourist," Tokarev said before launch. "With his approach, he's a real researcher."

Tokarev and McArthur are set to spend about six months aboard the ISS and conduct at least two spacewalks during their time in Earth orbit.

Both men are spaceflight veterans - McArthur flew three times aboard NASA space shuttles, while Tokarev has one shuttle flight under his belt - and have each flown to the ISS at least once in their spacefaring careers.

"I really must say that a career in astronautics, a career in being an astronaut, is occasionally a significant professional and personal commitment," McArthur said before flight, referring to the support of his wife and two daughters who were at Baikonur Cosmodrome for the space shot. "I will always be grateful that the three women in my life have been at each of my...launches."

McArthur had hoped to return to Earth in May 2006 aboard a NASA space shuttle, though ISS mission officials said Thursday that he will likely ride aboard Soyuz TMA-7 with Tokarev during an April 2006 decent. The launch of NASA's next shuttle mission is in question as the U.S. space agency recovers from damage caused by Hurricanes Katrina and Rita and continues ongoing troubleshooting to solve launch debris problems with space shuttle external tanks.

"With this expedition we're kind of getting ready for the return to flight of the space shuttle next spring," Gerstenmaier said.

The space shuttle Discovery is slated to launch the STS-121 mission - a second orbiter test flight to evaluate fixes made after the loss of Columbia and its crew in 2003 - in March 2006, though NASA officials have said the flight may likely fly later in May 2006. The STS-121 flight will follow Discovery's recent STS-114 mission.

But despite the shuttle's delay, it is vital for the completion of the space station, which McArthur said is key for NASA's vision of sending human explorers back to the moon and on to Mars.

"We don't have the answers we need to send people to Mars yet," McArthur said. "We know a lot of the questions, but we need to have the space station to answer those questions."

• Complete Coverage: ISS Expedition 12
• Complete Coverage: ISS Expedition 11