Discovery's payload bay is taken up with the Italian-built Multi-Purpose Logistics Module (MPLM), which acts as a giant packing box on shuttle logistics missions.

BBC: Faulty valve halts shuttle launch

The Leonardo Multi-Purpose Logistics Module, an aluminium canister loaded with almost five tonnes of equipment, systems and science racks for transfer to Destiny, will be attached to the ISS early next week.

BBC: Discovery docks with space station

That was the ultimate purpose of the Space Station, and the arrival of this module will enable us to do that.

WHITEHOUSE: President Obama's call to the International Space Station