Soyuz lifts off with Kelly, Kaleri and Skripochka. Photo Credit/NASA TV

A Soyuz rocket carrying NASA’s Scott Kelly and  Russians Alexander Kaleri and Oleg blasted off from the Baikonur Cosmodrome in Kazakhstan late Thursday, initiating a five to six month voyage aboard the International Space Station.

The launching at 7:10 p.m., EDT, placed the three men on course to dock with the orbiting science laboratory on Saturday at 8:02 p.m., EDT.

“I’m convinced everything will go as planned,” Kelly said in pre-launch remarks broadcast by NASA TV. “I know this crew is prepared.”

The three men will join the station’s current crew, Americans Doug Wheelock and Shannon Walker and Russian Fyodor Yurchikhin. Kelly is slated to assume command of the station, as Wheelock, the current skipper, Walker and Yurchikhin depart the station for Earth in late November.

“You have done everything you could do to prepare for the flight,” Sergei Krikalev, the head of the Russian Space Agency’s Gagararin Cosmonaut Training Center told the three men as they left their Baikonur dormitory for the launch pad. “Good luck.”

During their stay on the space station’s newcomers are expected to host the last of NASA’s scheduled space shuttle assembly missions. Discovery is scheduled to lift off on Nov. 1 with a new equipment storage module called the Permanent Multipurpose Module and Robonaut 2, a humanoid robot. Robonaut 2 is scheduled to undergo a series of tests to determine its suitability as an aid to astronauts for activities outside as well as inside the station.

Endeavour lift off on the last scheduled shuttle flight is tentatively scheduled for Feb. 27.  The final mission will deliver the $2 billion Alpha Magnetic Spectrometer, an external astronomical observatory for studies of dark matter and anti-matter, little understood materials created by the Big Bang.

Endeavour’s skipper, Mark Kelly, is Scott’s twin brother. If the scheduling holds, their meeting will be the first between blood relatives in space.

“It will be great to have two shuttle visits while I’m up there, especially having one at the beginning and one at the end,” said Scott Kelly. “Having my brother on the last one will make it even more special.”

Scott Kelly, left, Alexander Kaleri, right, during the Soyuz TMA-OM1 climb to orbit. Oleg Skripochka, not picturered, is seated to the right. Photo Credit/NASA Photo

Initially, STS 134 was to fly in mid-2011. The flight was postponed to accommodate changes to the AMS.

“We will see what happens, whether we launch on time or not,” said Mark Kelly, who traveled to Baikonur to witness his brother’s launching. “If we do, then when I open the hatch, he will be on the other side.”

In addition to hosting NASA’s final shuttle missions, the space station crew anticipates a flurry of unmanned cargo ships launched by the European and Japanese space agencies as well as the Russians.

The station’s six tenants also intend to ramp up scientific research.

“You will have plenty of good work to do,” Bill Gerstenmaier, NASA’s chief of space operations, assured the three fliers as they prepared to lift off. “You will be very busy, but take some time to enjoy yourselves.”