TURIN, Italy —

The Italian-built Node 2 –

now called Harmony –

that has arrived at the international space station is a sophisticated module that provides electrical power and environmental control

, increases the amount of experiment-storage and crew walk-around room,

and provides five available docking ports for other

elements of the orbital facility still to come.

It is the first of two nearly identical modules built by ThalesAlenia Space here and flown to the station as part of an elaborate barter arrangement between NASA and the European Space Agency (ESA).

NASA is scheduled to launch Europe’s Columbus habitable laboratory to the station in December aboard a U.S. space shuttle, a mission

that is being paid for by European hardware that NASA will use.

Node 2/Harmony, like Columbus and ESA’s

Automated Transfer Vehicle (ATV) cargo carrier – the first of which is scheduled for launch in January –

are based on the same hull design produced here by ThalesAlenia Space. Node 2/Harmony will provide the docking ports for

Columbus and for

the Japanese Experiment Module, Kibo, laboratory to be launched in 2008. Another

port will be used for a planned Japanese cargo carrier whose launch date is uncertain.

While often referred to as connecting modules and passageways, Node 2/Harmony and the nearly identical Node 3, to be launched in 2010, are necessary elements if the station is to be capable of supporting a permanent crew of six astronauts.

Dino Brondolo, director of infrastructure programs at ThalesAlenia Space, said the two nodes will provide water recycling and oxygen production in addition to their role in adding workspace and connections for other modules.

“For us, the arrival of Node 2 is really the beginning of the internationalization of the space station,” Brondolo said. “Without it, neither the European nor the Japanese laboratories could be attached.”

Once docked to the U.S. Destiny module, its permanent location, Node 2/Harmony

will require

some 34 days and five spacewalks to fully activate its systems and prepare it

for the December arrival of Columbus, Brondolo said.

Node 2/Harmony, with a launch mass of some 14,300 kilograms and measuring 7.2 meters long, is about as big as the Columbus laboratory. Node 3, which is nearing completion here, is the same basic structure but with several additions, including an astronaut treadmill.

The barter agreement between NASA, ESA and the Italian Space Agency that led to the development of the two nodes was signed in 1997 and includes other ESA-provided gear such as

a freezer and a refrigerator.

Following several months during which Node 3 financing was stalled by a disagreement between ESA, the Italian agency and the Node 3 contracting team, responsibility for both nodes’ development was transferred to ESA in 2004.

Node 2 arrived at NASA’s Kennedy Space Center, Fla., in June 2003. Node 3 is expected to be completed by the spring of 2009. Italian authorities hope to be able to secure a shuttle launch for Node 3 several months earlier than the currently planned date of April 2010.

Luigi Maria Quaglino, general manager of the Turin production facility, said the Node 2 and Node 3 contracts totaled about 300 million euros ($429

million) for ThalesAlenia Space.