The Death Star was an enormous military battle station in the fictional Star Wars universe. Two of them were built over the course of the series (although the real model, about 2 1/2 feet in diameter, currently resides in Seattle's Sci-Fi Museum); they are enormous space stations capable of destroying a planet completely.

The Galactic Empire's ultimate weapon, the Death Stars, were mobile battle stations that mounted a directed superlaser weapon capable of completely destroying a planet with a single shot (though the second Death Star was destroyed before demonstrating its full capabilities). Planetary shields that could have held off entire fleets were ineffective against such a weapon. The first Death Star held 27,048 officers, 774,576 crew including troopers, pilots and officials, 400,000 support workers and over 25,000 Imperial stormtroopers. These represent minimum crew figures, and the station could probably hold several times this number. It also carried assault shuttles, Skipray Blastboats, strike cruisers, drop ships, land vehicles, and support ships as well as 7,200 TIE fighters. For surface protection it sported 10,000 turbolaser batteries, 2,500 ion cannons and at least 700 tractor beam projectors, and the superlaser. Even without the primary weapon, the Death Star carried enough troops and ships to occupy an entire star system.

Two Death Stars (I and II) were featured in the original movie trilogy: the first in A New Hope, and the second in Return of the Jedi. The designs for the Death Star are visible in Attack of the Clones; and in Revenge of the Sith. Palpatine is seen viewing the plans before the war ends, and the basic structure of the first Death Star is seen near the end of the film.




The first Death Star was designed by the Geonosians under Poggle the Lesser. At the start of the Clone Wars, they gave the designs of their "Great Weapon" (also referred to as the "Ultimate Weapon") to Count Dooku to prevent the designs from falling into Jedi hands. Dooku took the designs back to Coruscant and gave them to his master, Darth Sidious. Once the war was well underway, the Separatist leaders began to finance and build the weapon, using mostly Geonosians as their laborers. Due to the changing political climate, the Separatist leaders were all murdered, the Separatist movement was ended and the weapon fell directly into the hands of the newly-formed Empire.

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. It is believed that enslaved Geonosians continued to work on the Death Star well into its construction, the initial stages of which were shown in the ending of Revenge of the Sith. According to the New Essential Chronology as well as statements made by George Lucas himself, this is the same Death Star seen in A New Hope. Despite this, some fans (including Dr. Curtis Saxton on his Star Wars Technical Commentaries website) have claimed that this Death Star must be a prototype to the one seen in the original film. The construction was delayed while a test system was created at Maw Installation, and after a long delay for systems testing, construction was resumed on the battlestation.

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 the droids R2-D2 and C-3PO) 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 pair of proton torpedoes down a thermal exhaust port that leads directly the reactor core, causing a chain reaction which destroys the battle station.



As mentioned in Return of the Jedi, Bothan spies steal the plans to the second Death Star (this information is also found in the book Shadows of the Empire), unaware that their theft was orchestrated by Palpatine (some missions in "The Emperor's Will", the last expansion campaign in the game Star Wars: TIE Fighter, allow the player to personally take part in this orchestration, including killing some—but not all—Bothan spies to preserve the illusion that the Empire was trying to prevent acquisition of the plans). General Crix Madine and Admiral Ackbar devise a plan for its destruction. Han leads a team to the forest moon of Endor to destroy its shield generator, while a group of fighters and the Millennium Falcon piloted by Lando Calrissian fly into the center of the ship through a narrow superstructure 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 to fire. However, 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. It is not clear whether the shorter recharge time applied only to the reduced-power shots used to destroy starships, or also full-power planet-shattering shots.

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 heat-dissipating ducts, 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, while the rest were spread across the surface.

The Death Star's turbolaser is powered by a hypermatter reactor. The hypermatter reactor powers the primary power amplifier. The power amplifier starts up the firing field amplifier, which creates an ultimate power that travels through the tributary superlaser beam shaft. Eventually, the ultimate power hits the carrier crystal beam, creating a superlaser with the power to destroy a planet. It has been calculated that overcoming the gravity holding together an Earth-sized planet takes on the order of 10³² joules of energy, or roughly the total output of the sun in a week. More detailed estimates place the violent destruction of Alderaan as requiring 1.0 × 10³⁸ joules of energy, or on the order of millions of times more than necessary to permanently break the planet apart. This is the equivalent of from 1.1 × 10¹⁸ to 1.3 × 10¹⁹ tonnes of resting matter converted directly into energy (by Albert Einstein's formula, ''E'' = ''mc''²). This is not to be confused with energy-TNT equivalence). This massive quantity of fuel leads to obvious problems if storage is considered. If the energy is produced by matter-antimatter annihilation with the reagents being stored in a sphere with a density of one tonne per cubic meter, this would give a ball of matter and antimatter fuel between 1,300 and 2,900 km in diameter. Even the 10³² joules estimated as the minimum to destroy a planet would require a 13 km globe of such fuel. The massive power-generation abilities of the Death Star are explicitly referred to in the factbook thusly: "In order to deliver a spectacular, planet-destroying burst, the station's hypermatter reactor would have to have been able to generate power equivalent to hundreds of super-giant stars".

The law of conservation of momentum also causes interesting problems for this weapon system; these and other problems led to dissent among some within the Star Trek vs Star Wars debate community, who dispute that the Death Star's reactor could (or did) supply this quantity of energy.

Calculations have also been made for the destruction of the moon of the planet Kessel by the prototype Death Star in Champions of the Force; assuming it to be similar in size and composition to Earth's moon, this would require 10²⁹ joules. A similar figure is proposed by the Essential Guide to Vehicles and Vessels, which claims that the prototype's firepower could destroy the core of a planet. Star Wars Technical Commentaries on the Death Stars

While some claim the Death Star is an inefficient way to destroy a planet, the films show that it was intended to be a weapon of ultimate power, where the threat of its use would deter star systems who might otherwise defy or displease the Empire. This policy was known as the Tarkin Doctrine. While the relatively simpler task of modifying a large asteroid's orbit would be an effective way to wipe out life on a planet, it would not have the same psychological impact as a weapon of the Death Star's magnitude being deployed. Planetary shields, seen in the Expanded Universe and surrounding the Forest Moon of Endor in Return of the Jedi, may also be the reason for deploying the Death Star rather than kinetic weapons. Such shields, designed to withstand planetary bombardments, could possibly also deflect asteroid impacts. Some claim that slow-motion viewing of the destruction of Alderaan, the first victim of the Death Star, implies the planet was protected by such a shield, as the blast seems to curve around the planet and envelope it before the explosion.