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It would seem that these satellites formed in such a way that lighter elements were depleted close to Jupiter or that water did not condense on Io and Europa because of their higher temperature near to Jupiter either during the condensation from the original nebula or as a result of subsequent heating of Jupiter . At first , under the tiny bulb , silence aches me . They are made of ice and dust , materials from the original nebula . Otherwise not only does the idea in fact remain extremely nebulous , but also the original nebula , as the deductions progress , really becomes ever thicker and more impenetrable ; ... A careful examination of the broken bulbs might show the place of initial breakage . For instance , the light which will allow one to see the great nebula in the constellation Andromeda tonight started coming through the frigid reaches of space before the first man walked on the earth . The inner nebula was depleted not only in the gaseous and icy components of the original nebula but also in those elements that are volatile below about 1100K . Thrilled with the power of the new telescope , William Cranch Bond wrote to President Everett of Harvard : " You will rejoice with me that the great nebula in Orion has yielded to the powers of our incomparable telescope ! Sirius flashing low , Orion 's belt with the great nebula swinging like a pendant of diamonds ; the ruby stars , Betelgueux and Aldebaran - - my eyes went up beyond these to Perseus shepherding the Kids westward along the Milky way . Then an adequate concentration of heavy elements ( metals ) was needed to provide the two percent ' rock ' and ' ice ' components of the original nebula .