Space Shuttle Atlantis and its crew of six astronauts arrived at the international space station Nov. 18 to deliver a load of massive spare parts for the orbiting laboratory, an effort that NASA expects to add years to the station’s life once the space shuttle fleet is retired at the end of 2010.

“We’re sending up 14 large spare parts for the space station — that’s probably the single largest number of spares we’ve sent up in a very long time,” said Eve Stavros, shuttle payload flow manager for the shuttle’s STS-129 mission. “We’ve sent a total of 17 in the six years prior to this mission, so 14 on one mission — that’s a lot.”

With only one U.S. module left to deliver, NASA is turning its attention to helping the space station build up a store of replacement parts. Only half a dozen flights remain in the shuttle’s manifest before the fleet retires. As the only vehicle large enough to carry many large pieces of equipment into space, several remaining flights will be devoted to this task.

For STS-129, station spares were sent up on two platforms, dubbed External Logistics Carriers, which astronauts are attaching to either side of the station’s truss for easy access. Stavros said the carriers hold a total of 12,386 kilograms of spares to keep the station going long after the shuttle retires. Some spares will be used to replace failed components of systems that provide the station power or keep it from overheating or tumbling through space. Others are essential parts of the robotics system that allows astronauts to replace worn-out parts.

In addition to the complex robotics work astronauts are conducting to move the spares into place, three spacewalks are scheduled, as well as a complicated rewiring project planned for the crew inside. Atlantis is due to return to Earth Nov. 27.