[5] Randall's hypothesis is similar to the Nemesis theory, which postulates that a currently unseen brown dwarf star orbiting the Sun is the cause of the periodic impacts.

[4] Physicist Konstantinos Dimopoulos offers that a proposal from a world-renowned cosmologist is certainly credible, but notes the "need to make dark matter weirder than it already is" violates Occam's razor.

"[7] Jim Al-Khalili, in a review published in The Wall Street Journal, describes the book as "a cracking read, combining storytelling of the highest order with a trove of information" on the underlying science.

[8] Maria Popova, writing for The New York Times, was less enthusiastic, saying while Randall is not one of the few "working scientists who are also enchanting writers", she is "an excellent explainer" with an "infectious" affection for the subject matter.

Popova notes the idea, due to a lack of confirming physical evidence, is "essentially a thought experiment", and that the book's "greatest reward" is actually "the gift of perspective".