题目内容:
Thenextgreatlandareathatmanhopestocolonizeisthemoon.InsizeitisnearlyequaltotheareaofNorthandSouthAmericas.However,itpresentsahostileenvironment.Temperaturesrangefrom+120to-150degreesCentigrade.Thereisnoair,nowater.Todaythereisconsiderablescientificspeculationaboutlivingonthemoon.Whenmanwillbeginlifeonthelunarsurfaceisstillnotdetermined.Butexpertsbelievethatcolonizationwilltakeplaceinthreesteps.First,therewillbeincreasingperiodsofexplorationwithtemporaryshelters.Theseperiodswillbefollowedbylongerstayswithhousingunderthesurfaceofthemoonanddailynecessitiesbroughtbythecolonizersthemselves.Finally,coloniesthatareself-supporting
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