When Worlds Collide (film)

When Worlds Collide is a 1951 sci-fi film by George Pal. Based on a 1933 novel, it follows a group of astronomers who discover that a star is on a collision course with Earth. They work to build a spaceship to carry a small group of humans to a passing planet in an effort to save humanity.

This is often considered the first true impact event film and one of George Pal's best works.

This film contains examples of:

 * Adaptation Name Change. Bronson Alpha and Beta from the book become Bellus and Zyra.
 * Diesel Punk: A differential analyzer (admittedly at the cusp of its own obsolescence in 1951) is used to calculate Bellus's course.
 * Hey, It's That Guy!: Diehard Star Trek fans will recognize Stanton as Dr. Philip Boyce from the original pilot, "The Cage", as well as a three-armed Martian from The Twilight Zone.
 * Money to Burn: David does this after learning the world is ending.
 * Retro Rocket: The Ark, although it's not a tail-sitter (it launches from a gigantic ramp).
 * Sci-Fi Writers Have No Sense of Scale: Dr. Hendron says that Bellus is exactly three billion miles from Earth. That is precisely the orbit of Neptune, and it is hard to imagine that a star heading for Earth wouldn't be seen long before getting that close.
 * The second line of the film says that Bellus and Zyra have moved a million miles in two weeks. Later, upon hearing they are three billion miles away, David laughs and says people will need to worry in a hundred years. At that speed and from that distance, it would take a hundred years to hit Earth, not the eight months that pass in the film.
 * What Might Have Been: Cecil B. DeMille considered making an adaptation soon after the novel's publication in The Thirties. In addition, Pal wanted to make a sequel based on After Worlds Collide.
 * What Happened to the Mouse?: In the first half of the film, there are passing mentions that similar rockets are being built in other nations. However, after the passing of Zyra, there is absolutely no mention of whether these ships were completed and made it off the planet.
 * The book's sequel described the fate of the other ships: the French ship crashed in the Alps on takeoff, the British ship landed in a lake on the new planet, and the broad Asian ship lands successfully and tries to claim the new world as its own.