 Dwarf planets, such as Ceres, Pluto and Eris, and small Solar System bodies are similar to terrestrial planets in the fact that they do have a solid surface, but are, on average, composed of more icy materials (Ceres, Pluto and Eris have densities of 2.17, 1.87 and 2.52 g·cm−3, respectively, and Haumea's , Makemake's and Gonggong's density is 2.02, 1.98 and 1.75 respectively g·cm−3).The Earth's Moon has a density of 3.4 g·cm−3 and Jupiter's satellites, Io, 3.528 and Europa, 3.013 g·cm−3; other satellites typically have densities less than 2 g·cm−3.The uncompressed density of a terrestrial planet is the average density its materials would have at zero pressure.