CAPE CANAVERAL, Fla. -- Two astronauts stepped out Thursday for NASA's first Thanksgiving Day spacewalk to hook up the plumbing on the international space station's newest addition, a 45-foot high-tech beam.
It was the second spacewalk this week for shuttle Endeavour crewmen Michael Lopez-Alegria and John Herrington, the first American Indian in space. They got an early start to the afternoon's work.
First on their to-do list was connecting fluid lines on the $390 million space station girder that was delivered by Endeavour. Ammonia eventually will flow through the pipes to cool the complex.
The big event of the spacewalk, though, was slated for the very end.
The plan called for Herrington to grab onto the 600-pound rail cart that was launched atop the beam and carry it over to the girder on the opposite end some 50 feet away, and then fasten it to an identical cart already there. Adding to the drama, the astronaut was going to ride on the end of the space station's 58-foot robot arm for the half-hour operation and be swung almost 200 degrees from one girder to the other.
The carts are intended for use by spacewalkers during space station construction. Lopez-Alegria and Herrington planned to try out the newest one before its relocation.
NASA wants the two carts attached to a bigger and more elaborate railcar that is used to transport the space station's robot arm, in order to keep the tracks clear for crane operations.
For now, these tracks stretch 134 feet over three linked girders. By the time eight more girders and sets of track are connected end to end over the coming year, the framework will extend 356 feet and support giant solar wings.
Herrington and Lopez-Alegria, both 44-year-old Navy pilots, will conduct a third and final spacewalk Saturday to wrap up work on the new girder. Herrington, a member of the Chickasaw Nation, became the first American Indian in space with Endeavour's launch last Saturday.
Lopez-Alegria sent holiday greetings earlier in the day to Mission Control.
"We all miss our families and we're sorry that you all are having to work on Thanksgiving, but it's all for a good cause," he said.