International Space Station

The International Space Station is an important step in expanding the human presence in space.  It is a habitat for the crew, a port for smaller vehicles, and a laboratory.  On it crew members from around the world have conducted research on the long-term effects of space travel on humans, gained valuable knowledge on microgravity construction, life support, robotics, and plant life.  From it they have observed the universe and Earth.

Currently two vehicles can dock with the station and return to earth, the Soyuz and the Space Shuttle.  Unlike the original Soyuz from the mid 1960s, the modern version can accommodate differently sized crewmembers, has an improved landing system and contains digital electronic controls and displays.  One Soyuz rocket is always docked to the ISS as an escape pod. In late summer 2009 a second Soyuz will be docked to the station which will allow a full-time crew of six to be evacuated at any time. The United States Space Shuttles Orbiter/Discovery, Atlantis, and Endeavour have brought the larger construction payloads the ISS and facilitated crew rotation.

The shuttle is resupplied via the Progress rocket, from Russia, and the European Automated Transfer Vehicle (ATV).  These are designed to berth with the space station and supply dry cargo, atmospheric air, water and propellant.  These rockets can also take away trash and waste product.  The rocket and cargo is incinerated during reentry.  A similar rocket, the Japanese H-II Transfer Vehicle (HTV), is scheduled to launch in September 2009.