 These may contain all the ingredients for life (water ice, ammonia, and carbon-rich compounds), including significant amounts of deuterium and helium-3.Since Dyson's proposal, the number of trans-Neptunian objects known has increased greatly.Colonists could live in the dwarf planet's icy crust or mantle, using fusion or geothermal heat and mining the soft-ice or liquid inner ocean for volatiles and minerals.