Three astronauts blasted off today from Russia's Baikonur Cosmodrome towards the International Space Station in an upgraded Soyuz spacecraft.
First-time astronauts Kathleen Rubins of NASA and Takuya Onishi of the Japanese space agency set off for a four-month mission at the ISS with two-time Russian cosmonaut Anatoly Ivanishin at 0136 GMT.
"And lift-off!" said a commentator on NASA TV, which broadcast footage of the launch in Kazakhstan.
The trio's launch was delayed by over two weeks as Russian space officials carried out further software tests on the modified vehicle.
Features of the new Soyuz series include upgraded boosters, an improved navigation system, strengthened shielding from debris and more cells on the craft's solar panels.
NASA's Rubins will be the first woman aboard the ISS since Italian Samantha Cristoforetti returned to earth with the record for the longest single spaceflight by a woman (199 days) in June last year.
The molecular biologist, accepted into the space program in 2009, will also become the first person to sequence DNA in space during her mission.
Takuya Onishi, who trained as a pilot on Japan's largest commercial airliner is the eleventh Japanese national to enter space.
His journey to the ISS where he will participate in experiments connected to the Japanese space agency's Kibo program coincides with the Tanabata star festival celebrated across his homeland.
Flight Engineer Ivanishin has already logged over 165 days in space following his first mission at the ISS in 2011 and 2012.
The ISS space laboratory has been orbiting Earth at about 28,000 kilometres per hour since 1998.
