The Death Star is a moon-sized planetoid military space station in the fictional Star Wars universe.
The Galactic Empire's ultimate terror weapon, the Death Stars were battle stations several hundred kilometers in diameter and mounting a directed energy weapon capable of completely destroying an Earth-sized planet with a single shot. Planetary shields that could have held off entire Imperial fleets were ineffective against such a weapon. The first Death Star held at least 26,000 stormtroopers and over 7,200 TIE fighters.
Two such Death Stars were featured in the original movie trilogy, the first in A New Hope, and the second in Return Of The Jedi.
According to the Star Wars Incredible Cross Sections fact book, the first Death Star was 160 kilometers in diameter. According to the Inside the Worlds of the Original Trilogy fact book and detailed scaling of the station in the movie, the second Death Star was 900 kilometers in diameter. While some Expanded Universe sources and starwars.com state much smaller figures—120 kilometers for the first Death Star and 160 kilometers for the second—most of the evidence argues for the larger sizes.
The initial design of the first Death Star was done by the Geonosians. They gave the designs to Count Dooku to prevent the designs from falling into Jedi hands. Dooku took the designs back to Coruscant and gave them to Darth Sidious. Raith Sienar also had plans for a Death Star-like battle station. However, he later let Grand Moff Tarkin take credit for the design since he no longer had interest in the project.
In A New Hope, Han Solo and Luke Skywalker mistake the station for a small moon while following a lone TIE fighter. After escaping from the Death Star, the plans to the station, stolen by Rebel spies (according to the LucasArts video games, a secret signal interceptions asteroid, as well as Kyle Katarn), are transported by Princess Leia (with help from Han Solo, Luke Skywalker and two droids) to Rebel leaders. Luke Skywalker pilots an X-Wing starfighter through a trench-like indentation on the surface of the Death Star, evading a pursuing Darth Vader long enough to launch a proton torpedo down a ventilation tube that reaches right down into the "reactor core", causing a chain reaction to destroy the battle station.
In Return of the Jedi, Bothan spies steal the plans, unaware that their theft was orchestrated by Emperor Palpatine. General Crix Madine and Admiral Ackbar devise a plan for the destruction of the Death Star. Han Solo leads a team to the forest moon of Endor to destroy its shield generator, while group of fighters and the Millennium Falcon piloted by Lando Calrissian fly into the centre of the ship through a narrow maze of pipes and destroy the reactor directly, rushing out in just enough time to escape the ensuing explosion.
One drawback of the original design was the power systems. The first Death Star's reactor required one full day to generate enough energy for a full power shot. However, even low power shots were capable of massive destruction on a planetary scale. The second Death Star had redesigned systems and was capable of firing once every few minutes. It also had improved targeting computers, allowing it to fire the weapon at capital ships.
The second Death Star corrected several flaws of the original design. The two-meter exhaust vent that doomed the first station was replaced with millions of millimeter wide tubes, each designed to seal if excess energy was detected. The second station also boasted far more turbolaser batteries with redesigned targeting systems, allowing them to target starfighters more easily. The greatest concentration of turbolasers was located near the Emperor's throne tower.
In the early production of the original movie, the hollow dish was designed to be on the equator, but then it was decided to be on the 'northern' hemisphere. However this old design can still be seen in the grid plan animations seen in the movie. This is because the animation was created before the designer decided to change it. This is a blooper, since the original plan in Star Wars Episode II: Attack of the Clones shows the 'later' form.
At the same time of the first Death Star's construction, Sienar was designing a battlestation (apparently without a superlaser) of similar size and prestige as the Geonosian superweapon. The best elements of both were apparently merged together with final detail work taking place in the secret Maw Cluster near Kessel. This laboratory completed a scaled-down prototype that was later destroyed by the New Republic.
Several Star Wars expanded universe publications indicate that the primary designer of the Death Star was an engineer named Bevel Lemelisk. However, as Lemelisk's contribution is not mentioned to any degree in Star Wars: Episode II, it may be assumed his role was either not that significant, or that his character does not exist in the "official" on-screen Star Wars universe. Bevel Lemelisk would therefore by much the same kind of character as another prominent expanded universe figure: Grand Admiral Thrawn.
Durga the Hutt also built a small version with only the central laser core and a small living quarters, which was destroyed in the asteroid field around Hoth. This was known as the Darksabre but shoddy construction techniques meant that this attempt was an abject failure even before its destruction.
Many of the Star Wars games are concerned with the Death Star's destruction, or the theft, protection, and transmission of its plans.
It has been calculated that blowing up an Earth-sized planet takes on the order of 1032 joules of energy; this is roughly the total output of the sun in a week. More detailed estimates place the violent destruction of Alderaan as requiring 1038 joules of energy, or roughly one million times that necessary to permanently break apart the planet. The energy total is probably slightly higher than this, as Alderaan's planetary shield withstood the blast for roughly 0.2 of a second.
The prototype Death Star destroyed the moon of the planet Kessel. While there was little detailed information about this event, it would have required around 1029 joules, assuming similar size and composition to Earth's moon.
Astronomers used the phrase "Death Star" to describe Nemesis, a hypothetical star body first postulated in 1984 that was supposedly responsible for gravitationally forcing comets and asteroids from the Oort Cloud towards Earth.
Internally, the logo of AT&T, due to its visual similarity, is known as the Death Star. When political cartoon and comic strip creators learned of this, many references to AT&T used the Death Star analogy. It was widely seen in Doonesbury and Bloom County comic strips. This name was also given to the titanic former Bell Labs facility in Holmdel, New Jersey, now owned by Lucent.
In the novel Virtual Light by William Gibson, the Los Angeles Police Department uses an orbital satellite for surveillance and communication; the police nickname it the Death Star.
The Death Star has been parodied in such shows as Futurama, which features the "Near-Death Star", an installation in which all U.S.E. (United States of Earth) citizens older than 160 years of age are kept in coffin-like containers plugged into a computer simulation of a nursing home in Florida (in the manner of The Matrix and similar films); also the Brainspawn's Memory Bank (a gigantic memory bank twice the size of three ordinary memory banks), used in a hellish plot to understand and destroy the universe.
In the Oedekerk Entertainment film Thumb Wars: the Phantom Cuticle, the Death Star equivalent is called the Thumb Star or the Death Thumb and looks rather a lot like a thumb. In the true Evil style of Black Helmet Man, it carries weapons capable of destroying a planet (efficiently labeled the "One Huge Weapon Thing"), as well as several thousand Smaller Ineffectual Weapon Things, ten thousand Thumbtroopers, five thousand Thumbperial Battle Technicians, two thousand Fist-Fighter Pilots, and three bathrooms.
The Sonic the Hedgehog villain Dr. Robotnik built the "Death Egg", an obvious parody of the Death Star (but with his own mugshot plastered on) used to conquer the world in Sonic 2 and Sonic 3 & Knuckles. It was destroyed, so he went on the make a parody of the second Death Star, the "Death Egg 2" in the arcade fighting game Sonic the Fighters which blew up again.
A reference to the Death Star was also mentioned in the box-office comedy hit "Austin Powers: The Spy Who Shagged Me" (1999). In the movie, the villain - Dr. Evil - was just revived from his cryogenically frozen state after several decades, and was contemplating on several innovative evil schemes to achieve his objective of world domination. Dr. Evil suggested that he will create a new superweapon device by attaching a gigantic "laser" on the moon and then attempt to destroy Washington D.C. with the weapon. Since he was frozen when the Star Wars movies came out, Dr. Evil wasn't aware of the Death Star from the Star Wars universe. He amusingly dubbed his newly formulated device - "the Death Star" - thinking he was the first person to ever conceive of such a sophisticated weapon ingeniously.