A three-man crew has blasted off from a space centre in southern Kazakhstan on board a Russian-made Soyuz craft for a half-year stay at the International Space Station.
Nasa astronaut Joseph Acaba and Russian cosmonauts Gennady Padalka and Sergei Revin set off from the Baikonur facility as scheduled.
Russia's space agency said the craft is due to dock with the space station on Thursday morning and will join the three astronauts currently staying at the orbiting laboratory.
The crew will immediately begin preparation for the arrival next week of privately owned SpaceX's Dragon Capsule. It will be the first time a private company has launched space station supplies.