International Space Station program ocean was found to be possible only with Russia's assistance. At the time ISS was launched, the Russian Space Agency had experience from de-orbiting the Salyut 4, 5, 6, and 7 space stations, while NASA's first intentional controlled de-orbit of a satellite (the Compton Gamma Ray Observatory) would not occur for another two years. NASA currently has no spacecraft capable of de-orbiting the ISS at the time of decommissioning. Skylab, the only space station built and launched entirely by the US, decayed from orbit slowly over 5 years, and no attempt was made to de-orbit the station using a deorbital
Earth Departure Stage Earth Departure Stage The Earth Departure Stage (EDS) is the name given to the proposed second stage of the Block 2 Space Launch System. The EDS is intended to boost the rocket's payload into a parking orbit around the Earth and from there send the payload out of low Earth orbit to its destination in a manner similar to that of the S-IVB rocket stage used on the Saturn V rockets that propelled the Apollo spacecraft to the Moon. Its development has been put on hold (though not abandoned) until stages capable of transferring heavy payloads to Mars are required