Planet-killer

In science fiction, a planet killer, planet buster, planet cracker, planet glassing or similar variations on that meaning, is a fictional object or device capable of either destroying an entire planet or otherwise rendering it uninhabitable by a civilized species – a variety of a doomsday device. Examples of such devices include the Death Star from the Star Wars film franchise, the "Doomsday Machine" seen in the original Star Trek television series (though in both franchises ordinary spaceships like Imperial Star Destroyers and the Enterprise were also capable of killing a planet) or the atomic-powered stone burners from Frank Herbert's Dune franchise.

The term "planet-buster" has also come into use with reference to major natural disasters such as significant asteroid impact events or doomsday events.

Planet killers function in a variety of ways depending on the series. Weapons such as the Death Star and the titular ship in Lexx use a directed energy weapon capable of obliterating a planet in moments. In the game Spore, the planet killer is an antimatter bomb that is inserted in the center of the planet, causing the planet's core to split into countless fragments. Other weapons, such as the Shadow Planet Killer in Babylon 5 and Covenant warships in the Halo series, render a planet uninhabitable. The Shadow Planet Killer does so by firing missiles which burrow into the planet's core and detonate, causing planet-wide volcanic activity which renders the planet lifeless. Covenant warships use plasma weapons to superheat the surface of the planet; the crust is turned into a glass-like substance rendering it uninhabitable. In Star Blazers, missiles that can destroy a planet (and even a star) with a single hit exist.

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