One American and two Russians have taken off from Kazakhstan in a Soyuz craft. Two of the astronauts will be on the International Space Station for an entire year.
A Russian Soyuz spacecraft carrying two Russian cosmonauts and one US astronaut blasted off from the Baikonur Cosmodrome in Kazakhstan on Friday on a journey to the International Space Station.
"The flight is normal," Russian mission control said seconds after the launch.
Scott Kelly, 51, and Mikhail Kornienko, 54, will become the first to spend a full year on ISS. The third crew member, Gennady Padalka, 56, will stay on for six months, breaking the record for the most cumulative time in space while aboard the ISS.
The three will arrive at ISS, which orbits 400 kilometers (about 250 miles) above earth, around 6 hours after takeoff. Their year-long mission is to study the long-term effects of space travel as NASA considers manned flights to an asteroid and eventually Mars. A mission to Mars would take at least 260 days of travel.
Kelly is going to be the subject of a special experiment as the first American to spend a year in space. NASA will monitor his identical twin brother, a former astronaut, to compare the effects of space on their genetic makeup.
Three crew members -- Russian Anton Shkaplerov, Italian Samantha Cristoforetti and American Terry Virts -- are currently onboard the space station, due to leave in May.