Colonization of the inner Solar System Colonization of the inner Solar System Bodies in the inner Solar System have been considered for terraforming and space colonization. The main candidates for colonization in the inner Solar System are Mars and Venus. Other possible candidates for colonization include the Moon and even Mercury. The short distance between the Earth and the Moon makes it a natural expansion after Earth. A number of government space agencies have periodically floated lunar plans such as Russia (2014), China (2012) and the US have made plans in constructing the first lunar outpost. The European Space Agency (ESA) head Jan Woerner has proposed
Formation and evolution of the Solar System further hypothesized that the Mars-sized object may have formed at one of the stable Earth–Sun Lagrangian points (either or ) and drifted from its position. The moons of trans-Neptunian objects Pluto (Charon) and Orcus (Vanth) may also have formed by means of a large collision: the Pluto–Charon, Orcus–Vanth and Earth–Moon systems are unusual in the Solar System in that the satellite's mass is at least 1% that of the larger body. Astronomers estimate that the Solar System as we know it will not change drastically until the Sun has fused almost all the hydrogen fuel in its core into helium,