Macmillan published Worlds in Collision — then folded and handed Doubleday a bestseller

Immanuel Velikovsky was a physician and psychoanalyst who came to New York from Palestine in 1939. Worlds in Collision claimed that Venus and Mars had nearly collided with Earth in historical times, stopping the planet's rotation and producing the catastrophes behind the Exodus and other ancient texts. Eight publishers rejected the manuscript. Macmillan took it, published it on 3 April 1950, and listed it in its textbook catalogue — encouraged by Gordon Atwater, director of the Hayden Planetarium, who promised the author a sky show based on the book.

Harper's and Reader's Digest ran glowing pre-publication features; the book was an instant New York Times bestseller. The scientific community reacted differently. Harlow Shapley of Harvard — who had received Velikovsky's 1947 pamphlets — called its celestial mechanics irreconcilable with Newtonian physics: it violated conservation of energy and angular momentum. Shapley and Cecilia Payne-Gaposchkin opened a campaign against Macmillan, and the textbook catalogue was the lever: the book was listed under Science and mailed to professors, so they threatened a boycott of Macmillan's textbooks.

Within two months of publication, Macmillan transferred the book to Doubleday. Doubleday had no textbook division, so it was less vulnerable to pressure — and it reaped the reward. Worlds in Collision topped the New York Times bestseller list for eleven weeks and stayed in the top ten for twenty-seven. Velikovsky followed with Ages in Chaos (1952) and Earth in Upheaval (1955), and once campuses let him back in he lectured to record crowds across North America.

The affair became the defining test of how science treats popular pseudoscience. In 1974 the AAAS devoted a full symposium to Velikovsky, with Carl Sagan as the rebuttal; his critique judged that not one of Velikovsky's ideas was 'simultaneously original and consistent with simple physical theory'. Sagan also called the attempt to suppress the book 'the worst aspect of the Velikovsky affair'. It is still cited as the canonical example of pseudoscience and the demarcation problem, and Stephen Jay Gould's verdict: Velikovsky was 'neither crank nor charlatan' — just 'gloriously wrong'.