Friday's sunrise launch is to take three astronauts to the station, two of whom - Russian Sergei Krikalev and American John Phillips - plan to stay aboard for about six months. During that time, two shuttles are expected to dock with the station, more than two years after the shuttle program was suspended in the wake of the Columbia disaster, when the craft disintegrated upon re-entry.

For more than two years, Russia's space program has provided the only way of delivering astronauts to the station. Along with the Soyuz, Russia's unmanned Progress cargo ships also deliver supplies to the orbiting laboratory.

NASA aims to return the shuttles to flight this spring, perhaps as early as May 15, and Krikalev and Phillips both have experience to coordinate a shuttle docking.

Italian Roberto Vittori, flying for the European Space Agency, is to return April 25 with Leroy Chiao and Salizhan Sharipov, the American and Russian who have been aboard the station since October.

Locomotives lumbering at a walking pace towed the 161-foot gray-and-white rocket and Soyuz module, cradled horizontally on a rail car, to the launch pad at the Baikonur Cosmodrome, Russia's facility for manned space missions in Kazakhstan, where it was raised gingerly to vertical.

En route, preceded by a pair of policemen and a dog inspecting the tracks, the gleaming assembly passed through a dismal landscape highlighting the funding problems that have plagued Russia's space agency since the collapse of the Soviet Union: fields strewn with scrap, shabby hangars and the weather-beaten hulk of a derelict Buran, the Soviet Union's attempt to match the U.S. space shuttle program.

Mission commander Krikalev, 46, will be making his sixth flight into space, the most of any Russian cosmonaut.

In 2000, he was part of the mission that began permanent occupancy of the station, staying 4 1/2 months. If he returns to Earth as planned in October, he will have accumulated the most time of any human in space - more than 800 days. He also made three missions aboard Russia's Mir space station.

Phillips is making his second flight to the International Space Station. His first was aboard the shuttle Endeavour in 2001, and during the mission, he was coordinator of two spacewalks to install a remote manipulation system on the station. Launch day is his 54th birthday.

"I think being able to go into space is a pretty good present," his wife, Laurie, said as she watched the rocket being raised into place. "We're very excited that he's finally going after 3 1/2 years of training."

Vittori, 40, is to carry out experiments in biology and human physiology during his eight days on the station.

Experiments to be conducted during the long-term mission on the station include looking into muscle loss in space, kidney stones and radiation damage to chromosomes.

The three-stage rocket system is to bring the Soyuz to a speed of 13,420 mph within 7 1/2 minutes of liftoff. The three astronauts will spend two days inside Soyuz before reaching the space station.

         Complete Coverage: ISS Expedition 11