The crew on the U.S. space shuttle Endeavour is getting ready for Wednesday's docking at the International Space Station.
U.S. space agency NASA said crewmembers were working Tuesday on preparing the spacesuits that will be transferred to the space station for use during the mission's four spacewalks.
A NASA official has said the space walks will be "very demanding."
The crew is also inspecting Endeavour's thermal protection system using the sensor system attached to the end of the shuttle's robotic arm. The inspection is needed to make sure the heat shield was not damaged during launch.
This is Endeavour's last mission and the second-to-last space shuttle flight of the U.S. shuttle program.
Endeavour's main assignment is to install a $2 billion particle detector on the space station that scientists hope will help them learn more about the origins of the universe by searching for anti-matter and dark matter.
The shuttle and its crew of six lifted off from the Kennedy Space Center in Florida on Monday. The astronauts include five Americans and one Italian.
The mission is commanded by U.S. astronaut Mark Kelly, who is the husband of Gabrielle Giffords, a U.S. representative who was critically wounded in a shooting rampage in the state of Arizona in January. Doctors permitted Giffords to take a break from her rehabilitation to attend the launch.
The Endeavour mission originally was scheduled for late April, but electrical problems forced repeated delays. NASA crews worked over the past two weeks to complete repairs to the shuttle.
Endeavour will be retired when it returns on June 1 and put on display in Los Angeles. It began its first mission in 1992 and was the youngest of the three remaining U.S. space shuttles.
NASA will end the shuttle program with the scheduled launch of Atlantis in July. The third shuttle, Discovery, returned from its final flight in March. NASA is retiring the shuttles due to high operating costs and to free up funds to develop spacecraft that can travel farther into space.
After the final shuttle flight, the only way for astronauts to reach the orbiting research lab will be on Russian space capsules. Private U.S. companies hope to develop new spacecraft in the coming years that can resume the transportation of crews into space.
Some information for this report was provided by AP, AFP and Reuters.