page_title: International Space Station
section_title: Cancelled components
hierarchical_section_title: International Space Station / Structure / Cancelled components
caption_attribution_description: English: The U.S. Habitation module is lifted by crane during manufacturing at the Marshall Space Flight Center's Space Station Manufacturing Facility in Huntsville, Alabama. The Habitation module will be the living quarters for the crew of the International Space Station when it is launched in 2003. Visible in this photo on the right side of the module is one of two windows. Also visible is a hatch at the end of the module. The habitat module is 28 feet long and 14 feet wide. Fifteen countries led by the U.S. are cooperating to build the International Space Station, the first piece of which is scheduled to be launched in June 1998.
context_page_description: The International Space Station is a modular space station in low Earth orbit. It is a multinational collaborative project between five participating space agencies: NASA, Roscosmos, JAXA, ESA, and CSA. The ownership and use of the space station is established by intergovernmental treaties and agreements. The ISS program evolved from the Space Station Freedom, an American proposal in the 1980s to construct a permanently crewed Earth-orbiting station.
  The ISS serves as a microgravity and space environment research laboratory in which scientific experiments are conducted in astrobiology, astronomy, meteorology, physics, and other fields. The station is suited for testing the spacecraft systems and equipment required for possible future long-duration missions to the Moon and Mars. It is the largest artificial object in space and the largest satellite in low Earth orbit, regularly visible to the naked eye from Earth's surface. It maintains an orbit with an average altitude of 400 kilometres by means of reboost manoeuvres using the engines of the Zvezda Service Module or visiting spacecraft. The ISS circles the Earth in roughly 93 minutes, completing 15.5 orbits per day.
context_section_description: Several modules planned for the station were cancelled over the course of the ISS programme. Reasons include budgetary constraints, the modules becoming unnecessary, and station redesigns after the 2003 Columbia disaster. The US Centrifuge Accommodations Module would have hosted science experiments in varying levels of artificial gravity. The US Habitation Module would have served as the station's living quarters. Instead, the living quarters are now spread throughout the station. The US Interim Control Module and ISS Propulsion Module would have replaced the functions of Zvezda in case of a launch failure. Two Russian Research Modules were planned for scientific research. They would have docked to a Russian Universal Docking Module. The Russian Science Power Platform would have supplied power to the Russian Orbital Segment independent of the ITS solar arrays.
caption: The cancelled Habitation module under construction at Michoud in 1997
exif: {}