US space tourist Richard Garriott has successfully blasted off into space, following in the footsteps of his astronaut father.
Mr Garriott has paid about $30m (£17m) for his 10-day trip to the International Space Station (ISS).
The Soyuz TMA-13 spacecraft, mounted on a three-stage rocket, launched from Baikonur Cosmodrome, Kazakhstan, at 0701 GMT (0801 BST; 0301 EDT).
Richard's father, Owen Garriott, spent 60 days on a US space station in 1973.
He took extensive photographs of the Earth's surface during his stay on the Skylab orbital outpost.
Owen, 77, will support his son from mission control in Moscow.
Richard Garriott, a 47-year-old computer game designer, is joined on the flight by US astronaut Mike Fincke, who becomes the space station's commander, and Russian flight engineer Yuri Lonchakov.
The professional astronauts will supervise the start-up of new life-support equipment for the ISS. This should enable the full-time occupancy of the orbiting outpost to be increased from three to six crew members in May.
Mr Garriott has paid about $30m for his seat aboard the Soyuz
Richard Garriott is a board member and investor in Space Adventures, the US company that has brokered flights aboard Russian craft for five other millionaires, including the first paying space tourist, California businessman Dennis Tito, in 2001.
He plans to carry out experiments during his voyage, including one involving protein crystal growth, on behalf of companies that he says have footed a "meaningful percentage" of the ticket price.
Mr Garriott has also said he would take photos to record how the Earth's surface has changed in the 35 years since his father's voyage.
Mr Fincke and Mr Lonchakov will replace the station's current crew - commander Sergei Volkov and flight engineer Oleg Kononenko - who are due to return home with Mr Garriott on 23 October after six months in space.
By coincidence, Volkov became the world's first second-generation space traveller in April. His father is the cosmonaut Alexander Volkov, a veteran of long-duration spaceflights to the Russian Salyut 7 and Mir orbiting stations.
The cosmonauts have been investigating the cause of two recent off-target landings by Soyuz craft, believed to have been the result of faulty explosive bolts on the vehicles.
Mr Garriott spoke to BBC News in July about his ISS trip
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