Unloading of Atlantis' massive cargo begins

Jul 11, 2011, 18:53 GMT

Washington - Astronauts began transferring tons of spare parts and supplies from the shuttle Atlantis to the International Space Station on Monday.

Earlier they had used the ISS's robotic arm to remove the carrier full of the supplies from the shuttle's payload pay and attach it to the station for the duration of their stay. More than 130 man-hours will be needed to unload the cargo carrier and then to refill it with goods bound back for Earth.

Atlantis docked with the ISS Sunday on what is the last visit by a shuttle before the fleet is retired.

The 3.6 metric tons of supplies and spare parts are to keep the ISS stocked through next year.

Though the Russian, European and Japanese space agencies can all deliver equipment to the station, no other craft can carry such large heavy loads. NASA is working with commercial companies currently developing new spacecraft to deliver cargo, and eventually astronauts, to the ISS.

NASA hopes to add an extra day to the flight to allow more time to unload and also to load the shuttle with cargo headed back to Earth. The space agency will decide within days whether it can add the extra day, which would push back Atlantis' planned July 20 return, which was to coincide with the anniversary of the first moon landing in 1969.

Atlantis launched on its mission Friday from the Kennedy Space Centre in Florida, leaving a trail of sadness among the NASA workforce as well as fans after 30 years in orbit for the shuttle programme.

The ageing fleet is being retired due not only to long-standing safety concerns but also to free up funds to focus on developing a new spacecraft that will be able to reach more distant destinations.