Billionaire space tourist Charles Simonyi is saying farewell to the International Space Station as he prepares to return to Earth Wednesday to complete his second multimillion-dollar spaceflight.

Simonyi, the world's first repeat space tourist, is due to land tomorrow at 3:16 a.m. EDT (0716 GMT) when his Russian-built Soyuz spacecraft lands on the Central Asian steppes of Kazakhstan, where it will be afternoon when the capsules touches down.

The space station's outgoing crew — Expedition 18 commander Michael Fincke of NASA and Russian flight engineer Yury Lonchakov — will also return to Earth with Simonyi as they wrap up a six-month mission to the orbiting lab.

"Here's to a really good flight, and I'm hoping for a soft landing," Simonyi said in an audio message posted to his mission Web site, where he has been chronicling his mission.

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Simonyi, an American computer software developer, is paying about $35 million for a 13-day spaceflight under an agreement between Russia's Federal Space Agency and the Virginia-based firm Space Adventures. It is his second spaceflight and follows a 14-day flight in 2007, for which he paid about $20 million in a similar deal.

A native of Hungary, Simonyi launched to the station with two members of the outpost's new Expedition 19 crew on March 26 and arrived two days later. His flight was initially slated to last 12 days, but was extended by the Russian mission controllers in order to change landing zones when bad weather flooded the initial target.

Simonyi said he enjoyed the extra day in space, but was eager to return to Earth to his family and wife Lisa Perdotter, whom he married last year.

"I am very happy about the extra day, but it will be good to be back with my family for Easter," Simonyi wrote on his Web site. "The return trip will be only two hours from the closing of the hatch to touchdown."

Back to Earth

Unlike Simonyi, who is completing a nearly two-week flight, Fincke and Lonchakov are returning to Earth after spending half a year living and working aboard the space station.

The astronaut and cosmonaut performed two spacewalks and hosted two visiting NASA space shuttles during their mission. They worked to prime the space station to double its current three-person crew size later this year by installing, then repairing, vital life support equipment such as a urine recycler, second kitchen and second bathroom, as well as extra gym equipment. The station is expected to begin permanent six-person operations in late May.

"It's bittersweet," Fincke said. "I can't wait to see my beautiful wife and kids again, but I love the space station."

Fincke turned control of the space station over to Expedition 19 commander Gennady Padalka of Russia — who launched with Simonyi and NASA astroanut Michael Barratt — last week during an 11-day crew change.

Fincke, Lonchakov and Simonyi are expected to hold a brief farewell ceremony with Padalka and his two crewmates tonight at about 8:45 p.m. EDT (0045 April 8 GMT). They are then scheduled to undock their Soyuz TMA-14 spacecraft from the station at 11:52 p.m. EDT (0352 GMT) tonight, and then fire their spacecraft's engines at 2:24 a.m. EDT (0624 GMT) Wednesday in a braking maneuver to begin the descent back to Earth.

"It makes it even a little bit tougher because we have such a great crew, all six of us here at one time," Fincke said. "It's going to be really tough to shut the hatch and leave."

Space tourist Charles Simonyi is chronicling his second spaceflight on his Web site: www.charlesinspace.com.

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