Discovery's seven astronauts boarded the international space station tonight following a textbook docking by her commander as a combined 13 astronauts begin eight days together 220 miles above earth.
The hatches of both spacecraft opened at 9:33 pm EDT, and as Discovery's crew floated on board the orbiting outpost, the expedition 20 crew shook hands and hugged their newly arrived guests.
This will be only the second time in human space flight that 13 people are working and living on one spacecraft. NASA has prepared for this moment over past year by installing a second toilet (with a third on the shuttle), oxygen, a water purifier and extra supplies to support large crews.
Discovery's crew flying on her 37th mission includes commander Rick Sturckow, pilot Kevin Ford, and mission specialists Jose Hernandez, Patrick Forrester, John "Danny" Olivas, Christer Fuglesang (European Space Agency) and Nicole Stott.
Sturckow served as the pilot for the first space station assembly flight in 1998 when the two first pieces of the station were connected thus forming the nucleus of the space station complex.
Stott will switch places with current Station resident Tim Kopra at 11:30 pm, to begin a three month stay as a member of the expedition 20 and 21 crews on station. She will return home aboard Atlantis in late-November.
Up next will involve plucking the Leonardo MPLM (Multi-purpose logistics module) from the orbiter's payload bay with the station's robotic arm, and docking it to the station's Harmony port beginning on Monday afternoon. This is the module's seventh trip into space as a supply vessel.
Leonardo is a pressurized module full of 5,200 pounds of racks with experiments, supplies, and hardware -- including a huge freezer for storing new growth samples; a treadmill known as COLBERT which is arriving in two parts; and a new sleeping compartment for the recently expanded station crew.
Leonardo will be docked slowly to the station at 6:19 pm tomorrow.