The space shuttle Atlantis undocked from the International Space Station Sunday, after astronauts completed construction work on the station, and made preparations to return to Earth.

The space shuttle Atlantis pulled away from the International Space Station after three challenging space walks to install a pair of solar wings on the orbiting scientific station. The wings, which are 73 meters-long when unfurled, will eventually generate one-quarter of the space station's power.

After pushing off, Atlantis' pilot Chris Ferguson circled around the orbiting station so the astronauts could take pictures of it.

In a briefing with reporters, one NASA's flight director's, Phil Engelauf, said there were a lot of smiles around the space agency.

"The shuttle mission, although not over yet, has so far been just extraordinary successful in accomplishing the objectives that we set out to undertake in this flight," said Phil Engelauf.

On Monday, a camera mounted at the end of the orbiter's robotic arm will inspect the shuttle's nose cap and wing edges to look for any damage from space debris that could threaten the safety of the astronauts on re-entry.

The Atlantis' 11-day mission is the first space station construction flight since the Columbia disaster in 2003. Seven Columbia crewmembers were killed when the shuttle disintegrated on re-entry into Earth's atmosphere.

Two shuttle missions since the disaster were on shuttle Discovery. They were designed mainly to ensure the safety of the shuttle program.

Atlantis returns to Earth on Wednesday.

On Monday, a Russian Soyuz rocket carrying a cosmonaut, an American astronaut and the world's first female space tourist, blast off for the international space station.

Anousheh Ansari is an Iranian-American businesswoman who is reportedly paying $20 million to fly into space. Ansari will conduct several blood and muscle experiments for the European space agency.