Columbus, the latest laboratory for the International Space Station (ISS) is a first for the European Space Agency and another major step on the road to completing assembly of the world's largest spacecraft.

Expected to be launched aboard NASA's Space Shuttle Atlantis on Saturday 8 December, the EADS Astrium-built Columbus laboratory module will be unberthed from the orbiter's payload bay on flight-day four of the 11-day STS-122 mission and docked with the ISS Harmony module. Harmony itself was delivered by the Shuttle Discovery in October.

The culmination of 12 years' work, the laboratory's arrival also inaugurates ESA's part ownership of the station. The laboratory is part of a total ESA investment in ISS of about €8 billion ($11.7 billion), less than 10% of the estimated total cost of the ISS, which the European agency says is at least €100 billion.

A 4.5m (14.8ft)-diameter cylindrical module, Columbus has a launch mass of 10,300kg (22,700lb) and shares its basic structure and life-support systems with the Italian Space Agency's multi-purpose logistics modules, which are carried to the ISS by Space Shuttles to deliver cargo.

Designed for a 10-year lifespan, Columbus has room for 10 international standard payload racks, eight situated in the sidewalls, and two in the ceiling area. It will allow astronauts to conduct experiments in life sciences, materials science and fluid physics. At launch Columbus is outfitted with five internal payload racks.

Once up and running work in the laboratory will be supported by ESA's Columbus Control Centre (Col-CC). Situated at the German Aerospace Center facility in Oberpfaffenhofen, near Munich, Germany, the Col-CC will monitor and co-ordinate European and non-European astronaut activities inside Columbus. The centre also holds overall responsibility for issues such as laboratory safety under the overall authority of the ISS mission control centre in Houston, Texas.

On flight-day three of STS-122 Atlantis will dock with Harmony and preparations will begin for Columbus' permanent home at ISS. Prior to Columbus unberthing from Atlantis the orbiter's robotic arm has to be removed using the station's remote manipulator to enable the laboratory to be moved from the payload bay.

On flight-day four the mission's first of three 6.5h extra-vehicular activities (EVA) will see German-born ESA astronaut Hans Schlegel and NASA's mission specialist Rex Walheim attach the power and data grapple fixture to the European module. The power and data grapple fixture will allow the space station's robotic arm to grab the module and move it from the shuttle's payload bay to Harmony's starboard docking port a transfer that will also occur on day four.

They will also begin work to remove the ISS nitrogen tank assembly, a part of the station's thermal control system, from the P1 truss. The assembly needs to be replaced because the nitrogen is running low.

It was in October 1995 that ESA's ministerial council gave the go-ahead for the agency's involvement in ISS that would include the Columbus orbital facility.

The following year a €658 million contract was signed with the DASA, which later became part of EADS Astrium. In today's euros the module's cost is estimated at around €880 million. In 1997 ESA signed a barter agreement with NASA to have Columbus launched by Shuttle in return for the European provision of the ISS' node modules two and three. And now 10 years later STS-122's flight-day five will see astronauts enter the docked module for the first time. Day six will see the outfitting of the module begin.

On day eight Walheim and his Atlantis colleague Stanley Love, during STS-122's third EVA, will install two experiment payloads on Columbus' exterior. They are Solar, an observatory to monitor the sun, and the European Technology Exposure Facility that will carry eight different experiments requiring exposure to the space environment.

With the Atlantis crew's work done, Schlegel's fellow ESA astronaut on the mission, French-born Léopold Eyharts, will stay on board ISS and become a flight engineer for the station's current expedition 16 crew. He will return to Earth on board Shuttle Endeavour, scheduled for February. Eyharts says: "It is the first time that Europe will have, in space, a permanent science laboratory that will be attached to the ISS and it will be used over the next 10 years to perform scientific experiments."

Although the agreed policy of the ISS international partners - NASA, ESA, the Canadian space Agency, the Japan Aerospace Exploration Agency and Russia's Federal Space Agency - is to continue using the station until 2016, there have been discussions about extending its lifespan. Designed to explore the unknowns of microgravity science, the big question for Columbus now is whether it will end its life in 2016 or carry on working until the rumoured end-date of 2020.

Source: Flight International