"Enormity" does not mean "big", Mr. Science Fiction Author. Every time your character leans against the porthole and gazes out at the "enormity of the universe", I want to beat you to your knees with an unabridged dictionary. Enormity refers to monstrous wickedness: Your hero can gaze in wonder at the enormousness of the red deserts of Mars and in horror at the enormity of the cannibal feasts taking place thereon.
Enormity, however, is such a perfectly cromulent word that the rare chance to use it properly in a sentence should never be missed. To wit:
Those of you in business for yourselves can speak with aplomb on the sheer immensity of regulatory compliance and how it strangles the provision of goods and services in America.You know, Bill, "enormity" would have worked perfectly there.