|The Atlantis and ISS separated on Tuesday, marking the end of the US government's final space mission [Reuters]
A space shuttle has left the International Space Station to begin the journey back to earth at the end of the final mission in the iconic NASA spacecraft's 30-year career.
Atlantis undocked early on Tuesday morning, hours after astronaut crews aboard the shuttle and the space station traded farewells as they soared nearly 350km (217 miles) above the Pacific Ocean.
"Thanks so much for hosting us. It's a great station, and it's been an absolute pleasure," Atlantis commander Chris Ferguson said of his crew's nine-day stay at the space station after the final shuttle was launched earlier this month.
"We'll miss you guys. Godspeed, soft landing and we'll see you back on Earth," space station crew member Ronald Garan, a NASA flight engineer, said as Atlantis floated freely away.
"Farewell ISS, make us proud," Ferguson replied.
The shuttle then spent several minutes gradually pulling back to a distance of 182 metres in order to assess some of the modules and equipment that other missions have not had a view of.
With the conclusion of the US shuttle programme, astronauts will fly to space from other countries until a new commercial launcher and capsule, built by a private corporation, launches sometime around 2015.
Before leaving, the Atlantis crew gave their station colleagues a small US flag that flew on the inaugural shuttle voyage in 1981.
The flag is the prize for the first rocket maker that brings people from the US back to the station, launching from their country.
US President Barack Obama described it last week as "a capture-the-flag moment here for commercial spaceflight."
Atlantis, which delivered several tons of equipment and supplies to stockpile the ISS, is scheduled for a predawn landing on Thursday at Florida's Kennedy Space Center.