Ready to Fly: Next ISS Crew, Space Tourist to Launch Today

Two Russian cosmonauts and an American billionaire are gearing up to launch into orbit today on a flight bound for the International Space Station (ISS).

Expedition 15 commander Fyodor Yurchikhin, flight engineer Oleg Kotov and American entrepreneur Charles Simonyi -- the fifth paying tourist to the ISS -- are set to launch aboard their Soyuz TMA-10 spacecraft at 1:31 pm. EDT (1731 GMT) from Baikonur Cosmodrome on the Central Asian steppes of Kazakhstan.

"Very few people know that the pad we're going to lift off from in Baikonur is the very first pad that the very first Sputnik was launched and, later of course, the first human Yuri Gagarin in 1957 and 1961, respectively," Simonyi said in a prelaunch press conference, adding that 2007 marks the 50^th anniversary of spaceflight. "So in some sense we'll be leaving from that historical site."

Simonyi, a Hungary-born computer software developer, is reportedly paying between $20 million and $25 million for a 13-day flight to the ISS under an agreement arranged with Russia's Federal Space Agency and the Virginia-based firm Space Adventures. His close friend Martha Stewart and 50 other friends have made the trip to Baikonur Cosmodrome to watch his planned space shot, Simonyi has said.

Simonyi and the Expedition 15 crew are due to arrive at the ISS on April 9, though the space tourist will return to Earth April 20 with the station's Expedition 14 crew and is documenting his spaceflight on his website www.charlesinspace.com.

"I don't like this word 'tourist,'" Yurchikhin said of Simonyi in a prelaunch briefing, adding that the American entrepreneur has several tasks to perform during liftoff. "He will be one of our crewmembers, a real crewmember, who has a lot of jobs in space."

Yurchikhin and Kotov will mark Russia's first pair of long-duration cosmonauts to serve together aboard the space station since the Expedition 5 mission in 2002. They plan to perform three spacewalks during their six months aboard the orbital outpost, join NASA astronaut Sunita Williams already aboard, and receive several visiting space shuttle crews to continue ISS construction.

The cosmonauts will replace Expedition 14 commander Michael Lopez-Alegria and flight engineer Mikhail Tyurin, who have lived aboard the ISS since September 2006 and were joined by Williams in December. They also plan to host NASA's next shuttle mission, STS-117 aboard Atlantis, in May or June to receive a new set of solar arrays, then welcome NASA astronaut Clayton Anderson -- Williams' replacement -- during the STS-118 spaceflight later this summer.

A fifth Expedition 15 crewmember, NASA astronaut Daniel Tani, could also join the crew if his STS-120 shuttle mission to deliver the station's new Harmony node launches during the six-month station increment.

"We hope we will see Dan Tani," Yurchikhin has said.

But while the Expedition 15 crew looks ahead to their long mission, Simonyi is eagerly waiting to begin his own trip after a lifelong interest in human spaceflight that began in his youth where, at age 13, he served as Hungary's Junior Cosmonaut.

"Being inserted into orbit and approaching the space station, seeing it in its new glory, I think, will be a magic moment," Simonyi said in a prelaunch briefing.

NASA will provide live launch coverage on NASA TV beginning at 12:30 p.m. EDT (1630 GMT). Click here for live Expedition 15 mission updates and SPACE.com's NASA TV feed.

• IMAGES: Space Tourist, Expedition 15 Crew Train for Launch
• VIDEO: Space Tourist Charles Simonyi in Zero G!
• Complete International Space Station Mission Coverage