US Orbital Segment

The USOS consists of all modules forward of PMA-1

The US Orbital Segment (USOS) is the name given to the components of the International Space Station (ISS) constructed and operated by the US National Aeronautics and Space Administration, European Space Agency, Canadian Space Agency and Japan Aerospace Exploration Agency.

The segment currently consists of seven pressurised modules, an Integrated Truss Structure and various other unpressurised elements, which together essentially comprise the base configuration of the cancelled US Space Station Freedom. The segment is controlled from various mission control centres spread around the globe, including MCC-H, Col-CC, ATV-CC, JEM-CC, HTV-CC and MSS-CC.