Billionaire space tourist Charles Simonyi and two crew from the International Space Station (ISS) have safely returned to Earth.
The Soyuz capsule carrying the trio touched down on the steppes of Kazakhstan at 1631 (1231 GMT).
Mr Simonyi, a Hungarian-born US software engineer, paid $25m (£12.7m) for his 10-day stay on the ISS.
The 58-year-old is the fifth person to pay for a trip into space.
On his two-day journey to the ISS Mr Simonyi travelled with two replacement crew for the space station.
He returned to Earth along with Russian Mikhail Tyurin and US astronaut Miguel Lopez-Alegria, who have both been on the ISS since September.
Another US astronaut, Sunita Williams, has remained on board with newly arrived cosmonauts Fyodor Yurchikhin and Oleg Kotov of Russia.
Mr Simonyi, who amassed a fortune through his work on computer software, including helping to develop Microsoft Word and Microsoft Excel, is the 450th person to enter orbit and, by his own admission, "the first nerd in space".
Among the cargo he carried with him was a gourmet meal of roast quail marinated in wine and duck breast, selected by American lifestyle guru Martha Stewart, a friend of Mr Simonyi.
While on board the space station, Mr Simonyi carried out a series of experiments including measuring the amount of radiation he was exposed to during his stay.
The aim was to help to generate an accurate map of the station's radiation environment.
Mr Simonyi began training for the flight six months ago at the Yuri Gagarin Cosmonaut Training Centre in Star City, Russia; and at the Baikonur Cosmodrome in Kazakhstan.
He underwent a gruelling physical programme, including strict medical tests, to prepare him for the ride to escape the Earth's atmosphere and his time on board the ISS.
His trip was arranged by US-based Space Adventures.
The firm has previously sent four private explorers to space:
- American Dennis Tito in 2001
- South African Mark Shuttleworth in 2002
- American Greg Olsen in 2005
- Iranian-born US businesswoman Anousheh Ansari in September 2006.