International Space Station program with on-orbit refurbishment in mind. According to the Outer Space Treaty the United States is legally responsible for all modules it has launched. In ISS planning, NASA examined options including returning the station to Earth via shuttle missions (deemed too expensive, as the station(USOS) is not designed for disassembly and this would require at least 27 shuttle missions), natural orbital decay with random reentry similar to Skylab, boosting the station to a higher altitude (which would simply delay reentry) and a controlled targeted de-orbit to a remote ocean area. The technical feasibility of a controlled targeted deorbit into a remote
Geostationary orbit orbit, which Clarke first described as useful for broadcast and relay communications satellites, is sometimes called the Clarke Orbit. Similarly, the Clarke Belt is the part of space about above sea level, in the plane of the equator, where near-geostationary orbits may be implemented. The Clarke Orbit is about in circumference. Most commercial communications satellites, broadcast satellites and SBAS satellites operate in geostationary orbits. A geostationary transfer orbit is used to move a satellite from low Earth orbit (LEO) into a geostationary orbit. The first satellite placed into a geostationary orbit was the Syncom-3, launched by a Delta D rocket