What If?: Serious Scientific Answers to Absurd Hypothetical Questions to make them shatter on contact?" The book was received positively by critics. Ethan Gilsdorf of the "Boston Globe" stated that "it’s fun to watch as Munroe tackles each question and examines every possible complication." According to Gilsdorf, "What If?" gives a view into "Munroe’s playful yet existentially-tinged worldview" by contrasting cataclysmic scenarios with more heady ideas, such as examining the effects of a magnitude minus-7 Richter scale earthquake. The "Huffington Post" remarked that "What makes Munroe's work so fantastic is a combination of two elements: his commitment to trying to answer even the weirdest question with solid science, and
Absolute magnitude using an absolute magnitude, one must specify the type of electromagnetic radiation being measured. When referring to total energy output, the proper term is bolometric magnitude. The bolometric magnitude usually is computed from the visual magnitude plus a bolometric correction, . This correction is needed because very hot stars radiate mostly ultraviolet radiation, whereas very cool stars radiate mostly infrared radiation (see Planck's law). Some stars visible to the naked eye have such a low absolute magnitude that they would appear bright enough to outshine the planets and cast shadows if they were at 10 parsecs from the Earth. Examples