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From right, Hungarian-born U.S. software designer and space tourist Charles Simonyi, Russian cosmonaut and crew commander Gennady Padalka and U.S. astronaut Michael Barratt pose together in Baikonur, Kazakhstan, on Saturday. The crew is to blast off for the international space station from the Baikonur cosmodrome on Thursday in a Russian-made Soyuz capsule. ((Mikhail Metzel/Associated Press))

Recession or no, billionaire Charles Simonyi couldn't pass up another shot at space, even if it meant shelling out $35 million US more.

Besides, it may be one of the last times the Russian government allows tourists to hitch a ride to the International Space Station.

"It's now or never," said Simonyi, who has now spent $60 million US for a couple of space vacations. The first was $25 million US.

A computer genius who helped build Microsoft, Simonyi will become the world's first two-time space tourist when he leaves Earth behind Thursday. He'll be accompanied by two professional astronauts — a Russian and American — who will be going up for a six-month stint at the space station.

His own trip will last less than two weeks, and it will be his last.

"I'm not getting any younger," the 60-year-old told the Associated Press in a recent telephone interview. He'll be one of the older men to fly in space, though nowhere near John Glenn's record at age 77.

Besides, he's promised his new wife, Lisa Persdotter, a 28-year-old Swedish socialite, that this will be his final spaceflight. He told her about his plans when they got engaged and "she was very supportive, but, BUT to a limit, mainly. Just once," Simonyi said with a chuckle.

He's quick to point out this is his first marriage, and he's taking one of their engagement rings with him into orbit.

NASA concerns eased

The Hungarian-born Simonyi, who lives in suburban Seattle, is among six rich people who have bought tickets to space through Virginia-based Space Adventures.

NASA, the major stakeholder in the space station, may not love the idea of hosting tourists — "spaceflight participants" as it calls them. But the initial concerns back in 2001 have eased over the years with the addition of guidelines.

Space station program manager Mike Suffredini has spoken to Simonyi, just as he has with everyone going up, to make sure the visitor understands his limitations at the orbiting complex.

"It really has to do with their safety," as well as the safety of the others and the space station itself, Suffredini said. "They're extremely restricted" in what they can do on the American side.

All this may soon be moot: Russian space officials have indicated that after this year, there will be no more seats available to tourists. That's because the space station crew is about to double in size to six — hopefully by the end of May — and professional fliers will fill all the slots.

After he returned from his two-week space station trip in April 2007, Simonyi said Russian cosmonauts told him how different and rewarding it was to go back up a second time. With doors closing on future tourist flights, Simonyi did not want to miss out.

Because the training for his first flight was so recent, Simonyi got the abridged version, three months at cosmonaut headquarters in Star City, Russia, versus six to eight months before. He will return to Earth on April 7 in a Soyuz capsule.