The U.S. space agency NASA says the doors of the International Space Station's newest addition have been opened and several astronauts ventured inside for the first time.
Space station commander Jeff Williams opened the hatch into the module, known as "Tranquility," Friday night. He was followed into Tranquility by the commander of the Space Shuttle Endeavour, George Zamka, and several others. The team is working to set up the mechanisms inside the module.
Later, the door to Tranquility's observatory dome, called the "cupola," was also briefly opened.
Astronauts had attached Tranquility during a more than six-and-a-half-hour spacewalk that ended early in the day. The 792-cubic-meter observatory will provide spectacular views of the Earth and allow station personnel to monitor spacewalks outside the station.
The shuttle docked with the International Space Station Wednesday, two days after taking off from the Kennedy Space Center in Florida.
Four more shuttle missions are planned before the end of the year, when the shuttle fleet is retired.