Michael Lopez-Alegria acknowledged he changed his originally negative attitude to space tourists when he saw how two of them - Iranian-born Anousheh Ansari, a U.S. businesswoman, and Hungarian-born Charles Simonyi, a founder of Microsoft Corp. - who went to the ISS as space tourists adapted to space conditions and helped crewmembers in their work.
Lopez-Alegria, Simonyi, Russian flight engineer Mikhail Tyurin and German European astronaut Thomas Reiter shared their experiences from the mission.
Simonyi, the fifth space tourist in history, said his space-themed Web site had generated over 30 million visitors and added he was happy to let people learn more about the station and the Russian space industry.
The U.S.-based Space Adventures Ltd., the only company currently providing opportunities for space tourism, charges around $20 million per Russian-organized private mission.
The U.S. National Aeronautics and Space Administration had previously voiced concerns about the tourists' safety and usefulness.