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
Halo orbit 1996. It used an orbit similar to ISEE-3. Although several other missions since then have traveled to Lagrange points, they typically have used the related non-periodic variations called Lissajous orbits than an actual halo orbit. For example, Genesis, launched in 2001, which also pioneered the use of dynamical systems theory to find low-energy transfers to and from its orbit. In May 2018, Farquhar's original idea was finally realized when China placed the first communications relay satellite into a halo orbit around the Earth-Moon point. In January 2019, the Chang'e 4 spacecraft is scheduled to land in the Von Kármán crater