NASA is on track to launch the space shuttle Atlantis on Monday, but only if an unmanned rocket lifts off early Saturday as planned.

Six astronauts are slated to lift off aboard the shuttle on Nov. 16 at 2:28 p.m. EST (1928 GMT) from Launch Pad 39A at Kennedy Space Center in Cape Canaveral, Fla. They plan an 11-day mission to the International Space Station to deliver a cache of spare supplies.

"I'm happy to report that everything at Pad A is going well," NASA test director Charlie Blackwell-Thompson said during a briefing today. "We're not tracking any issues; all of our work is on schedule and progressing well."

The weather outlook is promising for Monday's launch, with a 90-percent chance of favorable conditions predicted.

"Overall the weather does look very good for launch," shuttle weather officer Kathy Winters reported.

The weather is also expected to cooperate for a scheduled United Launch Alliance Atlas V rocket launch Saturday at 12:48 a.m. EST (0548 GMT) from the nearby Cape Canaveral Air Force Station. If the satellite-bearing rocket cannot get off the ground Saturday, though, both that launch and the shuttle flight will be pushed back a day.

NASA crews shut Atlantis' payload bay doors this morning, enclosing a load of new parts for the station packed into two carrying containers planned to be attached to the backbone of the orbiting laboratory. Payload manager Scott Higginbotham said stowing all the gear onboard the orbiter was an exceptionally tough job.

"It's been a very challenging campaign for us, but we're there," he said. "We're smiling today because we crossed the finish line and we survived."

Higginbotham said the ground teams faced many trials in coordinating so many new parts into the carriers and the job took longer than expected.

We have "two new carriers and a large number of parts," he said. "The hardware wasn't terribly kind to us along the way. It was far more difficult than any of us had envisioned when we began."

Nonetheless, they completed their work on time, and the orbiter is ready to go, he said.

Atlantis' six-astronaut team, led by commander Charlie "Scorch" Hobaugh, plans to spend today gearing up for launch. Hobaugh and pilot Barry Wilmore practiced landing at Kennedy Space Center this morning in a Shuttle Training Aircraft — a Gulfstream II jet modified to simulate the shuttle controls and handling.

The STS-129 mission is Atlantis' second-to-last planned flight. All of NASA's three space shuttles are set to be retired in about a year or two.