Shuttle docks with space station

The shuttle is delivering an Italian-built unit

A US space shuttle has arrived at the International Space Station as part of a two-week construction mission.

Shuttle Discovery performed a back-flip as it approached the ISS, allowing crew members to inspect its wings and nose for any launch damage.

The shuttle then docked with the orbiting space platform high above the Earth, both travelling at 28,000km/h.

Discovery lifted off from the Kennedy Space Center, Florida, on Tuesday.

On Wednesday, astronauts used a robot arm to check the shuttle's wings and nose for signs of damage in what has become a routine inspection since the loss of space shuttle Columbia in 2003.

Nasa engineers did not spot anything significant in a preliminary look at images captured during Wednesday's examination, said John Shannon, head of the mission management team.

New home

Shuttle flight STS-120, commanded by US astronaut Pam Melroy, will allow a change of crew at the ISS.

Astronaut Daniel Tani will replace the long-stay resident Clayton Anderson, who has spent nearly five months living on the orbiting platform.

In graphics: Space Station

Tani will remain on board until the next shuttle flight, set for December.

"I can't wait to settle into my new home," he said on Wednesday, after being woken to the song "Dancing in the Moonlight".

During five planned spacewalks, Discovery's seven-strong crew will install the "Harmony" unit to the space station.

Harmony has been built in Italy and its installation will be led by Italian astronaut and mission specialist Paolo Nespoli.

Harmony will be the first expansion of the living and working space on the station since 2001.

Harmony will connect Europe's Columbus lab to the space station

It will provide a passageway between three science laboratories: the existing US Destiny lab; the European Space Agency's (Esa) Columbus module; and the Japanese Kibo experimental units.

Built by Thales Alenia Space, Harmony weighs some 14 tonnes. It is seven metres long and 4.6m wide.

Its launch marks the start of a busy few months for Esa at the ISS. The Columbus laboratory is set to fly to the platform in December.

And then in January, the "Jules Verne" Automated Transfer Vehicle (ATV) will launch from Kourou in French Guiana on a re-supply mission.

The ATV can carry 7.5 tonnes of equipment, food, fuel, air and other items to the orbiting outpost.

It will be the biggest and most sophisticated spacecraft Europe has ever lofted into space. The ship has an advanced navigation and docking system that enables it to find its own way to the ISS.

When the US retires the shuttle in 2010, the ATV will be the main means of supplying the station.