ARCHEOLOGIA NUOVA

Da:"Reuters.com"

Astronauts install last U.S. room on space station

Astronauts Steve Bowen (L) and Alvin Drew (R) participate in the mission's first spacewalk as construction and maintenance continue on the International Space Station in this photo provided by NASA and taken February 28, 2011.

Credit: Reuters/NASA Handout

The final U.S. module is combination storage room and research lab. It previously was used to haul cargo to and from the station, a $100 billion project of 16 nations. The refurbished module, formerly known as Leonardo, was the primary cargo carried into orbit aboard the space shuttle Discovery, which blasted off February 24 for its 39th and final mission.

"After all these years of construction, it comes down to this," said NASA mission commentator Josh Byerly.

Discovery astronauts Nicole Stott and Michael Barratt used the station's robotic crane to pick up the 14-ton module, now known as the Permanent Multipurpose Module, from the shuttle's cargo bay and move it to a berthing port on the station's Unity connecting node.

At 10:05 a.m. EST (1505 GMT), the new module was snapped into place as the station soared 220 miles over Africa.

"Thank you for the storage module," radioed station commander Scott Kelly to Mission Control in Houston. "It's much needed."

Although the U.S. side of the station is complete, Russia plans to add a research laboratory to its section.

Construction of the station began on December 8, 1998, with the attachment of the shuttle-delivered Unity hub to the Russian-launched core module Zarya. Since then, crews have added three laboratories, a living room, connecting hubs, airlocks, docking ports and a seven-sided window room called the cupola.

Next month, the station is to receive its highest-profile and most expensive research instrument -- the $2 billion Alpha Magnetic Spectrometer particle detector, which will examine cosmic rays in hopes of proving information on how the universe was formed. It is the primary payload for the shuttle Endeavour, which is targeted for launch on April 19 on its last mission.

NASA plans a final cargo run to the station in June with the shuttle Atlantis carrying a year's worth of supplies. All the shuttles then will be turned over to museums. NASA Administrator Charlie Bolden said he expects to decide where the retired shuttles will go in April.

Discovery's arrival on Saturday brought the number of spaceships parked at the station to a record six, a milestone NASA had hoped to document with pictures and video for historical and engineering purposes.

For safety reasons, however, managers decided not to approve a plan for Kelly and two cosmonauts to board a Soyuz capsule for a 75-minute ride around the station for the photo shoot.

The Discovery crew will get to keep the extra day added to their mission on Monday so they can help get the station ready for operations after shuttle retirement.

NASA is switching from flying and operating its own ships to the station to purchasing freight delivery services -- and eventually crew transport -- from commercial U.S. providers.

The shuttle is due back at the Kennedy Space Center next Tuesday.

(Editing by Jane Sutton and Bill Trott)