----------------------------------- zodiak 29 Iul 2012 21:20 ----------------------------------- Marte are apa, ceea ce ajuta un proces de teraformare si este la limita zonei unde exista posibilitatea pentru apa in forma lichida, deci este cea mai buna posibilitate. Totusi ce am castiga dintr-un Pluto teraformat? The diameter of the core should be around 1,700 km, 70% of Pluto's diameter.Charonian surface appears to be dominated by less volatile water ice, and also appears to have no atmosphere. In 2007, observations by the Gemini Observatory of patches of ammonia hydrates and water crystals on the surface of Charon suggested the presence of active cryo-geysers ERIS, SEDNA, ... Sedna's surface composition is similar to that of some other trans-Neptunian objects, being largely a mixture of water, methane and nitrogen ices with tholins. Its surface is one of the reddest in the Solar System. Trujillo and colleagues have placed upper limits in Sedna's surface composition of 60% for methane ice and 70% for water ice.[30] The presence of methane further supports the existence of tholins on Sedna's surface, as they are produced by irradiation of methane.[32] Barucci and colleagues compared Sedna's spectrum with that of Triton and detected weak absorption bands belonging to methane and nitrogen ices. From these observations, they suggested the following model of the surface: 24% Triton-type tholins, 7% amorphous carbon, 10% nitrogen, 26% methanol and 33% methane.[33] The detection of methane and water ices was confirmed in 2006 by Spitzer Space Telescope mid-infrared photometry.[32] The presence of nitrogen on the surface suggests the possibility that, at least for a short time, Sedna may possess an atmosphere. During a 200-year period near perihelion the maximum temperature on Sedna should exceed 35.6 K (−237.6 °C), the transition temperature between alpha-phase solid N2 and the beta phase seen on Triton. At 38 K the N2 vapor pressure would be 14 microbar (0.000014 Atmospheres).