Commander Peggy Whitson and Daniel Tani spent hours hooking up power and heater cables and fluid lines between the space station and the Harmony compartment that was delivered by the shuttle last month. It was tedious, hand-intensive work.
"Yay! Got it," Whitson exclaimed after making a particularly difficult connection. "Those were hard."
Not long afterward, Tani commented on how strong Whitson looked.
"She's the king of the world," Tani shouted. "Queen," replied the space station's first female skipper, sparking laughter between the two.
The fluid lines - for carrying ammonia, a coolant - were in an 18½-foot, 300-pound tray. The spacewalkers removed the tray from its storage location on the space station, then lugged it over to Harmony and bolted it down. It was awkward to carry, and the spacewalkers took turns, careful not to bang anything.
While venting some of the hookups, frozen ammonia crystals floated out and bounced off Whitson. She checked her suit with a contamination detector to make sure none of the toxic substance got inside.
Later, harmless nitrogen gas vented out of a valve. "Oooooh," Whitson said, laughing. "Something coming out of my hand."
NASA cannot launch another space shuttle until the school bus-size Harmony is all hooked up, inside and out. Atlantis is supposed to blast off Dec. 6 with a European laboratory that will dock to Harmony. One of Harmony's other parking spaces is reserved for a Japanese lab.
As the spacewalkers struggled with stiff connectors more than 200 miles up, Atlantis' seven astronauts climbed aboard their ship for a practice launch countdown.
The space station's three residents have been working almost nonstop since Discovery's departure on Nov. 5, and just last week moved Harmony to its permanent location. This was their second spacewalk; a third and final outing is set for Saturday to attach another fluid tray to Harmony.
They've already volunteered to work on Thanksgiving.
"They are just a hard-charging, get-it-done crew," said Kenny Todd, a space station manager. "We'll have to make sure they understand that it's Thanksgiving, and take some time and take a breath."
As the seven-hour spacewalk wrapped up, Tani thanked flight controllers for their help and wished everyone a happy Thanksgiving. "You have a lot of smiling faces down here," Mission Control replied.
NASA is still trying to figure out how to fix a jammed joint that is needed to turn one of the space station's two sets of huge solar wings. Even though Discovery's crew returned samples of steel shavings clogging the joint, engineers were unable to ascertain which parts are grinding against each other.
The joint will probably need to be cleaned and fixed, a formidable task requiring as many as four spacewalks, before Japan's lab can fly next year. Astronauts on the next shuttle flight may squeeze in a joint inspection.
Early in the spacewalk, Tani reported some minor abrasion on the outermost layer of his right glove. He said it occurred while he was working with fluid line hookups. "Maybe not the big smoking gun we're hoping for, but something," he said.
Spacewalking astronauts have ripped their gloves three times over the past year on sharp station edges. NASA is hunting for those jagged areas.
Among those watching the morning spacewalk from Mission Control was Tani's wife, Jane. She got a big "Hi sweetie" from orbit.