"We congratulate Charles on his continued commitment to commercial spaceflight. We look forward to assisting him in preparation for the spring 2009 mission," Eric Anderson, president of the space tourism company, said.
Simonyi, 60, has estimated wealth of $1 billion, and became the fifth space tourist in 2007, paying $25 million for the flight.
Space tourists started flying to the International Space Station in 2001. Dennis Tito, an American businessman and former NASA scientist, became the first space tourist when he visited the ISS in 2001. He was followed by South African computer millionaire Mark Shuttleworth in 2002, and Gregory Olsen, a U.S. entrepreneur and scientist, in 2005.
In 2006, Anousheh Ansari, a U.S. citizen of Iranian descent, became the first female space tourist.
U.S. games developer Richard Garriott, 46, the son of former NASA astronaut Owen K. Garriott, will go into orbit for 11 days in October on board a Russian Soyuz TMA-13.
