Shuttle Discovery Docked Harmony Node to Expand Space Station in 2007

The International Space Station grew from the size of a three-bedroom house to that of a five-bedroom home on October 23, 2007. The space shuttle Discovery launched that day with the Harmony module attached. The mission, designated STS-120, delivered a critical utility hub that connected the station’s international components.

Harmony measures 14 feet wide and 24 feet long, roughly the length of a minibus. It houses the sleeping quarters for American astronauts. The module also serves as a connector for the European Space Agency’s Columbus laboratory and Japan’s Kibo research lab.

Astronauts first attached Harmony temporarily to the Unity node. After the shuttle left orbit, the crew used the station’s robotic arm to move the shuttle docking port at the Destiny module. They then berthed Harmony at its permanent location beside Destiny. This relocation cleared the path for future expansions.

The delivery marked the end of a six-year gap in new construction. The last new room added to the station before Harmony was Russia’s Pirs docking module in 2001. That module has since been discarded. Harmony provided five common berthing mechanisms that allow other structures to attach to the station.

Thales Alenia Space, an Italian company, built the module for NASA. It is the second hub module constructed by NASA, following Unity. The name was selected through a public contest. Inside, the module contains eight payload racks. Four are reserved for avionics, while the remaining four serve as storage or crew quarters.

The two-week STS-120 flight concluded with Harmony positioned at the forward port of the Destiny laboratory. It now links the Columbus lab on the starboard side and the Kibo lab on the port side. A docking port on the roof of Harmony allows visiting vehicles to park there.

The module continues to support station operations by providing a central connection point. Its presence enabled the addition of new laboratories and cargo access points that were not possible before its installation.