Space tourism needed to force evolution of space flight, U.S. scientist says

The U.S. scientist slated to become the third non-astronaut to visit the international space station on Friday acknowledged his nervousness on the eve of the launch and defended his joining the Russian-American expedition as a necessary step in the evolution of space flight.

"I will feel most relaxed and most happy when the rocket is taking off," Gregory Olsen said. "This has been two years of very hard work."

Russian cosmonaut Valery Tokarev and U.S. astronaut William McArthur joined with Olsen for last-minute medical checks and program reviews as engineers prepared to fuel the Russian-built Soyuz rocket. At a news conference, Olsen said he preferred the term "space flight participant" to "space tourist," reports the AP.