Updated

Astronauts moved an old docking port to a new spot on the International Space Station late Monday in the second straight day of tricky crane work 220 miles above Earth.

The astronauts used the station's 57-foot robotic arm to attach the old docking adapter, a cone-shaped connecting piece, from the top of the orbiting lab to the outboard end of its newest room Tranquility.

The crane work ended at 9:28 p.m. EST and came one day after a new observation deck was plucked from the end of the Tranquility module and attached to a bottom port, where its seven windows are expected to give astronauts unprecedented views of Earth and space.

The $27.2 million observation deck, called the Cupola, and the $382 million Tranquility module were both delivered by NASA's space shuttle Endeavour, which docked at the space station last week. They were built in Italy for NASA by the European Space Agency.

Station astronauts hooked up the electrical and plumbing lines for the observation deck to begin activating its systems. The metal shutters protecting the lookout's windows will be unlocked during a Tuesday spacewalk and may be opened for the first time by Wednesday or Thursday, mission managers said.

"The Cupola, I think, is really one of the most spectacular viewing platforms that we will have had in space like this," said shuttle flight director Kwatsi Alibaruho early Monday. "We're eagerly awaiting the release of the shutters and the first views from it."

The old docking adapter, called Pressurized Mating Adapter-3, was previously attached to the top of the station's Harmony connecting node. It was moved to the outboard end Tranquility, which is a bus-sized module attached to left side of the space station's central Unity node.

The 10-year-old docking port will be used as a small storage space and protect Tranquility's end cap from exposure to space, NASA officials said.

NASA engineers will keep a close eye on the docking adapter to make sure that a nearby space station radiator doesn't get too close to it. If it does, the docking port may have to be moved back to its original spot, mission managers said.

Endeavour's six astronauts and the five-man Expedition 22 crew on the International Space Station are expected to take a half-day off late Monday before preparing for the third and final spacewalk of their joint mission.

"With this crew, we haven't had to twist their arm too much to get them to take the appropriate amount of free time off," Alibaruho said.

Mission Control reminded the astronauts to be sure to look out the window and savor the view during their time off.

That spacewalk is slated to begin late Tuesday night and last more than six hours. Endeavour launched Feb. 8 and is due to depart the space station late Friday.

The shuttle is slated to land in Florida on Sunday night.

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