Atlantis touched down for a final time Thursday, ending its last mission to the International Space Station and bringing down the curtain on NASA's 30-year space shuttle program.

The shuttle and its four-member US crew cruised home to a predawn landing at Kennedy Space Center at 5:57 am (0957 GMT), closing an era of human space exploration for the United States and leaving Russia as the world's only taxi to the ISS.

"Atlantis is home, its journey complete. A moment in history to be savored," mission control's commentator in Houston said as the white orbiter, emblazoned with an American flag, rolled to a stop.

"Having fired the imagination of a generation, a ship like no other, its place in history secured, the space shuttle pulls into port for the last time, its voyage at an end."

Shuttle commander Chris Ferguson praised the thousands of people who worked on the shuttle program since its first space flight in 1981.

"The space shuttle has changed the way we view the world, it has changed the way we view our universe," he said.

"There was a lot of emotion today but one thing is indisputable: America is not going to stop exploring.

"Thank you Columbia, Challenger, Discover, Endeavor, and our ship Atlantis. Thanks for protecting us and bringing this program to such a fitting end. God bless all of you. God bless the United States of America."

Twin sonic booms were heard over Florida moments before the shuttle glided home to perfect summer weather with clear skies and hardly any wind at the Kennedy Space Center.

Earlier the crew woke to the song "God Bless America," in preparation for the bittersweet end to the storied shuttle career, 42 years after US astronaut Neil Armstrong became the first person to step foot on the Moon as part of the Apollo 11 mission.

The shuttle mission STS-135 comprised a nearly 13-day trip to restock the ISS for a year with several tons of supplies and food.

Over the course of the program, five NASA shuttles -- Atlantis, Challenger, Columbia, Discovery and Endeavour -- have comprised a fleet designed as the world's first reusable space vehicles.

Columbia exploded in 2003 and Challenger was destroyed in 1986 in accidents that killed a total of 14 crew members.

Those disasters left only three in the space-flying fleet and Enterprise, a prototype that never flew in space. The quartet will become museum pieces in the coming months.

Critics have assailed the US space agency for lacking a focus with the space shuttle gone and no next-generation human spaceflight program to immediately replace it.

The astronaut corps now numbers 60, compared to the 128 employed in 2000, and thousands of people are being laid off from Kennedy Space Center. But NASA chiefs say future missions to deep space should revive hope in the US program.

"The brave astronauts of STS-135 are emblematic of the shuttle program -- skilled professionals from diverse backgrounds who propelled America to continued leadership in space with the shuttle's many successes," NASA administrator Charles Bolden said in a statement.

"This final shuttle flight marks the end of an era, but today, we recommit ourselves to continuing human spaceflight and taking the necessary -- and difficult -- steps to ensure America's leadership in human spaceflight for years to come."

On Wednesday, Bolden said the space agency was committed to the goals set out by President Barack Obama to send humans to an asteroid in 2025 and explore Mars by 2030.

NASA is building a Multi-Purpose Crew Vehicle that it hopes will be able to reach that goal, while it turns over low-orbit space travel and space station servicing to commercial ventures.

A commercial launcher and capsule built by a private corporation in partnership with NASA may be ready to tote crew members as early as 2015.

Until the private sector fills the void left by the shuttle's retirement, the world's astronauts will rely on Russian Soyuz rockets for rides to the ISS. ksh/mlm