The “Doomsday Machine” was the self-operational interstellar robotic weapon responsible for the destruction of numerous planets in the star systems L-370 through L-374. It most likely originated outside of our galaxy. The machine was somewhat conical in shape with a round aperture on the wide end. It was several miles long and possessed a neutronium hull. The machine was self-sustaining; based on the machine's behavior and subsequent analysis of planetary debris left in its wake, it was theorized that the machine had been destroying planets to fuel itself. The machine’s weapon of destruction was an anti-proton beam that emanated from the “maw”-like aperture. It used a tractor beam to capture and consume the resulting debris.

Both the U.S.S. Constellation and the U.S.S. Enterprise faced off with the Doomsday Machine in 2267. The Enterprise had mapped the solar system L-370 and its seven planets the previous year. Upon returning in 2267, they found the star intact, but the planets were reduced to rubble and debris. They soon found the U.S.S. Constellation adrift, running on reserve power after receiving damage in a confrontation with the Machine. All crew except commanding officer Commodore Decker had abandoned ship and were subsequently killed when the Doomsday Machine destroyed the planet they had beamed down to.

The Machine was finally rendered inert when Captain Kirk of the Starship Enterprise sent the derelict Constellation into the maw of the machine, with the ship set to auto-detonate her impulse engines.

Ship Model (Physical)

As portrayed in Star Trek: The Original Series - "The Doomsday Machine" (TV, 1967) Described in the episode’s outline as a “kind of cylindrical ‘living atomic rocket’ …with a posterior rocket and a great anterior funnel-mouth big enough to swallow a ship”, the composition of the “Doomsday Machine” model was most likely a wire framework wrapped in heavy-duty aluminum foil. The inside of the cone was foil and thus able to reflect the light source. The exterior was wrapped with both the foil and an extra layer of what appear to be crumpled sheets of color gel, the thin sheets of polycarbonate filters that are placed in front of stage and studio lights for tinting and color correction. The gel was secured with Scotch tape.

The model was presumably built around the studio light that provided the light source. The flicker effect would have been added in after the fact using a moire effect, where two varied patterns are superimposed to create an optical illusion of waves or shimmers. The moire was then projected onto a still of the model.

“The Doomsday Machine” was written by Norman Spinrad, who based it on his unpublished novella “The Planet Eater”. It is one of five Star Trek: The Original Series episodes to be nominated for 1968’s Hugo award for best dramatic presentation, losing to the Harlan Ellison penned “The City on the Edge of Forever” from the show's first season.