The space shuttle Atlantis and its seven-astronaut crew undocked from the International Space Station on Wednesday as it prepared its return to Earth.
Atlantis lifted from the orbiting outpost at 0953 GMT. Pilot Barry Wilmore then circled the space station before firing the shuttle's thrusters twice at 1104 and 1132 GMT to leave the vicinity.
The shuttle moved away at 1.5 feet (0.46 meters) per second or about 4.5 miles (7.2 kilometers) per orbit, according to the US space agency NASA.
The astronauts are scheduled to land back on Earth at the Kennedy Space Center in Cape Canaveral, Florida at 9:44 am (1444 GMT) Friday.
They completed three spacewalks to install high-tech equipment on the ISS during an eventful 11-day mission that also saw mission specialist Randy Bresnik buoyed by the birth of his second daughter, Abigail Mae Bresnik, back on Earth late Saturday, shortly after his first ever spacewalk.
He got the news by private phone patch through mission control after the crew was awakened.
During their stay, the astronauts installed communications antennas and a wireless video system, changed the location of a monitor for electrical hazards, deployed a cargo attachment system and placed an oxygen tank and new scientific experiment outside the station.
Space station flight engineer Nicole Stott also hitched a ride aboard Atlantis on its return to Earth after a three-month stint aboard the ISS.
On Tuesday, European Space Agency astronaut Frank De Winne handed over command of the station to Jeff Williams, a veteran NASA astronaut who arrived at the space station in October.
De Winne, Russian cosmonaut Roman Romanenko and Canadian astronaut Robert Thirsk are due to leave the station for return to Earth aboard a Russian Soyuz capsule on December 1 after 188 days in space.
After Atlantis, just six space missions will remain in the shuttle program before the fleet's three orbiters are retired.
NASA's shuttle program is due to be mothballed next year, but the White House could still decide to extend it through 2011 to reduce America's future reliance on Russia for transporting astronauts to the space station.
The shuttle remains the only spacecraft that can carry heavy, bulky equipment that is key to maintaining the ISS, set to remain operational until 2020.
Last month NASA successfully launched the prototype Ares I-X rocket that it hopes will launch the Orion, a new generation of manned space exploration vehicle that is still under development.
Orion, which is not expected to be ready until at least 2015, is being designed to take a crew of up to six astronauts on flights to the International Space Station, or a crew of four on lunar missions lasting up to 210 days.
But America's human space flight program, which swallows up 10 billion dollars of NASA's 18-billion-dollar annual budget, is at great risk of being grounded.
A panel set up by President Barack Obama and tasked with assessing its future has said an additional three billion dollars a year is needed for NASA to meet its goals.