Updated

American billionaire Charles Simonyi, a computer software executive who paid more than $20 million to fly to the International Space Station aboard a Russian-built Soyuz capsule in spring 2007, will train for a second Soyuz trip to the space station in spring 2009.

Vienna, Va.-based Space Adventures announced Tuesday that Simonyi will be the first repeat customer since the company began organizing space missions for private citizens in 2001.

The company's sixth customer, Richard Garriott, son of NASA astronaut Owen Garriott, is scheduled to launch to the space station Oct. 12. He is paying about $30 million under an agreement between Russia's Federal Space Agency and Space Adventures.

"Having a repeat orbital client demonstrates to the world that participating in a space mission is truly a magnificent and awe-inspiring experience," Eric Anderson, president and chief executive of Space Adventures, said in a Tuesday statement. "It is also an excellent example that the marketplace is even larger than previously anticipated because of the potential occurrence of clients who fly on multiple occasions."

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A native of Hungary, Simonyi trained for six months before his 13-day mission to the International Space Station in April 2007. The flight set a world record for the longest privately paid human spaceflight.

Reaching space was a lifelong dream, he said at the time, adding that he represented Hungary as a Junior Astronaut during a trip to Moscow at age 13.

Simonyi detailed the mission on his Web site, charlesinspace.com. During the mission, he answered hundreds of questions submitted to his Web site, participated in a lower back muscle study, mapped the station's radiation environment and tested high-definition camera components.

He also collected samples of microbes living aboard the space station for a European Space Agency experiment.

Swimming in the weightless environment of space was extremely pleasant, though by the end of his spaceflight Simonyi said he was missing Earthly luxuries like showers and beer.

"You know, every part had its highlights, and they just kept coming and coming," Simonyi told SPACE.com after his first spaceflight.

While Simonyi paid between $20 million and $25 million for his first spaceflight, the cost of such trips to the space station has risen to no less than $30 million due to inflation and increasing costs in recent years, Space Adventures officials have said.

SPACE.com Senior Editor Tariq Malik contributed to this report from New York City.

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