Colonization of the outer Solar System is subject to only 0.01 rem a day. When NASA carried out a study called "HOPE" (Revolutionary Concepts for Human Outer Planet Exploration) regarding the future exploration of the Solar System, the target chosen was Callisto. It might be possible to build a surface base that would produce fuel for further exploration of the Solar System. The Keck Observatory announced in 2006 that the binary Jupiter trojan 617 Patroclus, and possibly many other Jupiter trojans, are likely composed of water ice, with a layer of dust. This suggests that mining water and other volatiles in this region and transporting them
The empire on which the sun never sets Empire". From the mid-nineteenth century, the image of the sun never setting can be found applied to Anglophone culture, explicitly including both the British Empire and the United States, for example in a speech by Alexander Campbell in 1852: "To Britain and America God has granted the possession of the new world; and because the sun never sets upon our religion, our language and our arts...". By the end of the century, the phrase was also being applied to the United States alone. An 1897 magazine article titled "The Greatest Nation on Earth" boasted, "[T]he sun never sets on Uncle