ISS space walk. Astronaut Jeffrey N. Williams holds on to a newly installed handrail on the exterior of the International Space Station (ISS). The section of the ISS seen is the pressurized mating adaptor (PMA-2), a linking unit. Williams and his colleagues did other repairs and additions to the ISS, including work on the interior. The Space Shuttle Atlantis flew this mission, STS-101 (19th-29th May 2000). The ISS is a joint effort between NASA, the European Space Agency, the Russian space agency, Canada, Japan and Brazil. It orbits at an altitude of 350 kilometres and will be over 100 metres in length. It is scheduled for completion in 2004.