"Moonfall," Roland Emmerich's latest exercise in fantasy destruction, is the second major movie to come out recently in which a huge space body is hurtling toward Earth and risks destroying all human life. In the other, "Don't Look Up," the menace is a comet, but the real story is the corruption of American politics and culture that prevents a rational response and leads to catastrophe. Whether the comet represents climate change (as the makers of "Don't Look Up" assert) or the COVID-19 pandemic (as fits the movie best), the celestial body is nonetheless only a MacGuffin, a pretext to expose the human follies that are the movie's subject. But, in "Moonfall," Emmerich is interested--really, really interested--in the moon. His obvious enthusiasm for the gloriously absurd science-fiction reconception of the moon drives the directorial pleasure principle, and it's infectious.