The US space shuttle Atlantis ended a two-day journey to the International Space Station on Sunday, slipping into a berthing port to deliver more solar-powered panels and a new crewmember to the orbital outpost.
Docking was at 3:38 pm EDT (1938 GMT) as the two craft sailed 220 miles over the western Pacific Ocean.
Before parking Atlantis, commander Frederick Sturckow slowly back-flipped the shuttle so the space station crew could photograph the ship's belly tiles, a key part of the protective shield needed to safely re-enter the atmosphere. The pictures will help NASA determine if the shuttle sustained any damage from debris impacts during Friday's launch.
So far, the only area that has caught engineers' eyes is a small section of insulation covering the shuttle's left maneuvering rocket pod. Images taken by the Atlantis astronauts showed a 4-inch-by-6-inch (10-cm-by-15-cm) section of the insulating blanket has detached.
"Although this does not appear to be a big issue, the teams are discussing several options," flight controllers wrote in an e-mail message to the crew.
Heat shield inspections dominate the first few days of all shuttle missions since the 2003 Columbia accident. Columbia had wing panel damage from a debris impact during launch and was destroyed 16 days later as it flew through the atmosphere for landing, killing all seven astronauts aboard.
The accident was triggered by a piece of the foam insulation that fell off the external fuel tank and hit Columbia as it climbed into orbit.
NASA redesigned the fuel tanks, bought new inspection tools and put together rudimentary heat shield repair kits. Atlantis' launch, the fifth since the accident, renewed concerns about the tank because it underwent extensive repairs to fix hail damage from a freak February 26 storm.
Atlantis' flight to the station, originally targeted for mid-March, was delayed three months for the repair work, prompting NASA to swap the US crewmember aboard the space station during the current mission, rather than waiting, as originally planned, for the next flight.
Rookie astronaut Clayton Anderson was added to Atlantis' crew for the ride up and station flight engineer Sunita Williams will be ending a six-month stay in space with her return on the shuttle.
Williams, who already has spent more time on spacewalks than any other woman, also will break Shannon Lucid's 188-day record, set in 1996, for the longest spaceflight by a woman.
"Tell Suni we have Clay aboard and he's ready to relieve her," Sturckow told station commander Fyodor Yurchikhin as the ships drew close enough for radio contact a few hours before docking.
The Atlantis crew was scheduled to board the station shortly after 5 pm EDT (2100 GMT) to begin a week-long joint mission.
The shuttle is carrying a 45-foot (14-metre) long, 35,678-pound (16,183 kg) aluminum structure that will become part of the station's exterior backbone and includes solar panels.
Its crew members are scheduled to perform three spacewalks to install the new parts and retract an old solar array.
NASA plans to fly 12 more missions to complete the station. It also wants to make two flights to store spare parts and service the Hubble Space Telescope a final time before its three-shuttle fleet is retired in 2010.