Europa, the fourth-largest moon of the gas giant Jupiter and the sun, is a subject in both science fiction and scientific speculation for future human colonization. Europa's geophysical features, including a possible subglacial water ocean, make it a strong possibility that human life could be sustained on or beneath the surface. The Artemis Project designed a plan to colonize Europa in 1997. According to the plan, scientists are to inhabit igloos and drill down into the Europan ice crust…