Charles Simonyi, the former Microsoft employee who oversaw the development of Word and Excel, has booked a second trip into space.

Simonyi has already enjoyed one space holiday, spending 12 days in orbit last Spring. He has now booked himself in for a second trip in 2009.

"Having a repeat orbital client demonstrates to the world that participating in a space mission is truly a magnificent and awe-inspiring experience," said Eric Anderson, president of Space Adventures.

"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."

Anderson did not say how much Simonyi would be paying for the trip, although the reported bill for his first orbital excursion was $20m. He will become the first repeat civilian astronaut.

Simonyi was at Microsoft for over 20 years, and introduced the company to object orientated programming and the concept of a central program architect to whom software teams report.

He left the company in 2002 to start a new firm called Intentional Software, built around the intentional programming system he developed at Microsoft research.