The U.S. space shuttle Atlantis is set to dock at the International Space Station Sunday.

The astronauts used their first full day in orbit Saturday to inspect the shuttle's heat shield for any damage from Friday's launch.

NASA says the four-member crew used the shuttle's robotic arm and an extension with cameras on the end of it to get a close-up look.

Imagery experts on the ground will examine the data to make sure the heat shield is still in good condition.

The inspection is standard procedure. In 2003, damage during launch caused the space shuttle Columbia to disintegrate when it re-entered Earth's atmosphere.

Atlantis is on the 135th and final flight of the 30-year-old U.S. shuttle program. The shuttle's crew is delivering supplies, spare parts and science experiments during the 12-day mission, which NASA has described as “pretty busy.”

The cargo is expected to bridge the gap in supply shipments for the space station until commercial enterprises take over delivery by the end of this year at the earliest.

An estimated crowd of 1 million people watched the historic lift-off in and around the Kennedy Space Center in Florida.

The end of the shuttle program leaves the United States without its own manned spacecraft.

NASA is ending the shuttle program to concentrate resources on deep-space exploration. The agency is working with several commercial U.S. aerospace companies to develop vehicles to replace the shuttles. Until then, Russia's Soyuz spacecraft will ferry U.S. astronauts to and from the ISS, while Russian, European and Japanese cargo spacecraft will continue their resupply and waste disposal missions to the station.

The four astronauts on Atlantis are Commander Chris Ferguson, Pilot Doug Hurley, Mission Specialist Rex Walheim and Mission Specialist Sandra Magnus. All four have flown on previous shuttle missions.