The payload bay of Endeavour as seen Friday with the P6 truss tucked inside. Photo: NASA TV/Spaceflight Now

The Endeavour astronauts closed in on the international space station Friday, checked out the ship's robot arm, inspected a $600 million set of solar arrays in the payload bay and tested the spacesuits two astronauts will wear during an excursion Sunday to attach the arrays to the orbital outpost.

"We've got an extremely nominal mission going," said flight director William Reeves. "We had a very good launch, we've got a very clean shuttle vehicle, we've got no anomalies we're working on the orbiter at this time. So we're totally by the flight plan."

Shuttle commander Brent Jett, pilot Michael Bloomfield, Joseph Tanner, Marc Garneau and Carlos Noriega spent the day getting Endeavour prepared for docking Saturday and for installation of the P6 solar array truss during a spacewalk Sunday.

"The crew is in great shape," Reeves said. "The crew is staying on top of the timeline and actually staying a little bit ahead.

"We have checked out all the suits for the EVA (spacewalk) the day after docking. We've checked out the robotic arm on the shuttle for the operations after we dock where we'll pick up P6 from the payload bay and put it in a thermal park position. It's fully operational, with no problems.

"We've checked out all the power units we'll be powering the P6 element with and starting it up with from the orbit and that all has checked out OK," Reeves said. "So (it's an) extremely clean flight."

Endeavour is scheduled to dock with the space station at 1959 GMT (2:59 p.m. EST) Saturday.

Station commander William Shepherd, Yuri Gidzenko and flight engineer Sergei Krikalev were asleep when Endeavour blasted off Thursday night. When they got up early today, Sandy Magnus, an astronaut in the space station control center in Houston, jokingly told Shepherd to "clean up the house and put the welcome mat out."

"We'll have everything ready," he replied. "We hope the crew of Endeavour is happy."

"Yeah, they were looking forward to seeing you guys, I know."

"Yuri says he hopes they will be at the station on time," Shepherd said.

It's looking good for that. We're going to try to uplink some launch video later today so you can see the launch."

Endeavour is scheduled to dock with the Earth-facing port of the Unity module. To make room for Endeavour, the station crew earlier today undocked an unloaded Progress supply ship from a nearby port on the Zarya module.

The Progress M1-4 vehicle was launched Nov. 16 (Nov. 15 EST) and docked with the Zarya module's downward-facing, or nadir, port two days later. The station's on-board crew unloaded the spacecraft over the past two weeks.

The Progress was undocked at 1623 GMT (11:23 a.m. EST) today. A few seconds later a rocket firing was carried out to drop the craft about a mile below the station. At that altitude, it will pull ahead by about six miles per orbit, according to NASA's mission control commentator.

Russian engineers are assessing the feasibility of redocking the craft early next year to provide additional trash stowage volume for the station's crew. But this is a thorny issue for NASA managers and it's not yet clear how it will play out.

The Progress is designed to carry out an automated docking with the space station using the Russian KURS guidance system. As a backup, a pilot on board the station can take over manual control using a joystick hand controller and a video monitor that shows the view a pilot would see if he or she was on board the Progress. The manual guidance system goes by the name TORU.

During final approach Nov. 18, the automatic guidance system failed, apparently because of a software error, and cosmonaut Yuri Gidzenko had to take over for a manual TORU docking.

Russian engineers believe they understand what went wrong with the automatic guidance system. But a redocking would have to be carried out by Gidzenko. An antenna used by the automatic rendezvous system from 200 meters in retracted during the initial docking attempt and it was not designed to be re-extended.

"We still have all 10 antennas working on the KURS to allow the far-field operations, to get us from the far out distance all the way up to 200 meters," said station flight director John Curry. "So that's no issue.

"If we did give the crew final permission for approach and docking, they would simply be repeating what they've already performed," he said. "We would be nominally doing a manual docking. Obviously, since it's been done before we feel comfortable it can be done again."

NASA managers said earlier they were opposed to another manual docking because that system has no backup. Should Gidzenko's controls fail, the Progress could fly out of control and possibly hit the station.

But Curry said the Russians want to press ahead in this case to test a software patch designed to correct the problem that derailed the first automatic docking attempt last month. From 200 meters in, however, the docking would be manually controlled by Gidzenko.

While engineers assess the issue, the Progress M1-4 vehicle will remain in a parking orbit well away from the station.