Space shuttle astronauts will bid farewell to the International Space Station Tuesday and begin the trip home after more than a week linked to the orbiting laboratory.

The shuttle Discovery is due to undock from the space station today at 3:26 p.m. EDT (1926 GMT) to end about nine days at the orbiting laboratory. The shuttle's seven astronauts delivered tons of supplies and new science gear, as well as a new crewmember for the space station's crew.

"It's been a really amazing experience working up here on the International Space Station, with 13 people working together as a big team," Discovery astronaut Christer Fuglesang of Sweden told Mission Control early Tuesday.

Once Discovery undocks from the station, shuttle pilot Kevin Ford will fly the spacecraft on a victory lap of sorts around the orbiting lab while his crewmates take photographs. The maneuver, known as a fly-around, is used to document the current state of the station.

Before flight, Ford said he was eagerly looking forward to flying Discovery around the station, but it will be a bit different today. Discovery's small maneuvering thrusters have been offline since the shuttle launched due to a leaky thruster. Ford will rely on the shuttle's larger thrusters for the shuttle's departure, something astronauts have trained for.

"I want to say only to have a safe trip and have a safe flight back," station commander Gennady Padalka, a Russian cosmonaut, told Discovery's crew late Monday.

Skywatchers in the United States and southern Canada will have several opportunities, weather permitting, to spot the shuttle and space station as they fly overhead. The best opportunities run through Wednesday.

Station stocked up on science

Discovery launched to the station Aug. 28 on a 13-day mission to deliver new supplies and science experiments. Three spacewalks were performed to retrieve old experiments from the station's hull, replace a massive coolant tank and tend to some other maintenance tasks.

Altogether, the astronauts delivered 18,548 pounds (8,413 kg) of supplies to the space station and are returning about 5,223 pounds (2,369 kg) of trash and surplus items back to Earth.

The nearly 11-year-old space station is now 84 percent complete, has an internal living space equivalent to the cabin of a jumbo jet, and weighs about 720,000 pounds (326,586 kg).

The astronauts also delivered a $5 million treadmill named after TV comedian Stephen Colbert.

Colbert won the naming rights for a new space station room in an online NASA poll earlier this year, but the space agency named the module Tranquility — the Apollo 11 moon base — to honor the 40th anniversary of the first manned moon landing. NASA named the new station treadmill the Combined Operational Load Bearing External Resistance Treadmill, or COLBERT, as a consolation prize.

The treadmill launched in more than 100 pieces but won't be assembled until later, after Discovery leaves and a new Japanese cargo ship arrives at the station in mid-September.

The shuttle also ferried NASA astronaut Nicole Stott to the space station to join the orbiting laboratory's six-person crew. Stott is beginning a three-month space mission and replaced fellow astronaut Tim Kopra, who has lived aboard the station for nearly two months and will return home aboard Discovery.

Kopra has said that he's looking forward to seeing his family again, and perhaps taking his first sip of beer in months after he lands. But the space station, he added, has secured a permanent place in his heart.

"I'm going to miss this place," Kopra said Sunday in a televised interview. "I'm going to miss the beautiful views, the sunsets and sunrises."

Discovery is due to land Thursday evening at NASA's Kennedy Space Center in Florida.