Discovery Delivered Harmony Node to Expand Station in 2007

The International Space Station underwent a major structural change on October 23, 2007, when Space Shuttle Discovery lifted off carrying the Harmony module. This delivery during the STS-120 mission marked a distinct shift in the outpost's growth trajectory, ending a six-year gap since the last new room was added.

Harmony measures 24 feet long and 14 feet wide, a span comparable to a standard minibus. Built by Italy-based Thales Alenia Space for NASA, the structure originally went by the designation Node 2. It serves as the second hub module for the station, following Unity, which is designated Node 1.

The arrival of the module expanded the station's interior volume from the size of a three-bedroom house to that of a five-bedroom house. Before this addition, the most recent new component had been Russia's Pirs docking module, which arrived in 2001 and has since been discarded from the structure.

Upon arrival, astronauts initially attached Harmony to the Unity node. After the shuttle departed, the crew utilized the station's robotic arm to move the shuttle docking port from the Destiny module. This maneuver cleared the forward port of Destiny for Harmony's permanent berthing, positioning it as a central link for future expansion.

The module features five common berthing mechanisms that act as connection points for other components. It now supports the European Space Agency's Columbus laboratory on its starboard side and Japan's Kibo laboratory on its port side. A docking port on the roof also allows visiting vehicles to park at the station.

Inside the 24-foot structure, eight payload racks organize the module's functions. Four racks are dedicated to avionics, while the remaining four handle stowage or serve as crew quarters. NASA's astronaut sleeping areas are located within this space. The name Harmony was selected through a public naming contest run by NASA.

The STS-120 flight lasted approximately two weeks. Following the shuttle's departure, the crew completed the relocation from the temporary berth at Unity to the forward port of the Destiny laboratory. This repositioning finalized the module's role as a primary utility hub for the expanding station.