Omega Directive
The Omega Directive (denoted by Ω) was a highly classified Starfleet general order requiring the captain of a starship to notify Starfleet Command immediately upon detection of an Omega molecule.

The directive also authorized the use of any and all means to destroy an Omega molecule, superseding all other regulations including the Prime Directive. The Omega Directive was deemed necessary because of the extreme power and consequently catastrophic threat to interstellar civilizations posed by even a single molecule. Knowledge of the Omega molecule and the Omega Directive was restricted to starship captains and flag officers. Captains received subsequent training on how to deal with the issue; however specialist teams were created to deal with crisis.

History
In the mid-23rd century, a team of 127 top-Federation scientists, led by the Starfleet physicist Ketteract, was working on a top secret experiment at a classified research station in the Lantaru sector. Research showed a single molecule of Omega contained the same power as a warp core, so theoretically a small chain could sustain a civilization indefinitely. Ketteract's goal was to create an inexhaustible power source, though Seven of Nine pointed out its potential use as a weapon. Federation cosmologists theorized that the Omega molecule once existed in nature for an infinitesimal period of time at the exact moment of the big bang; some even claimed Omega was the primal source of energy for the Big Bang.

The scientists were able to synthesize a single Omega molecule, which only remained stable for a fraction of a second. Upon its nearly instant destabilization, the research center was destroyed, killing all 127 scientists. An unexpected secondary effect (discovered by rescue teams en route) was the rupture of subspace within a radius of several light years, causing warp travel to become a permanent impossibility within this area. Starfleet Command realized the terrible implications: a chain reaction involving a handful of Omega molecules could devastate subspace throughout an entire quadrant, effectively ending interstellar travel for spacefaring civilizations in the quadrant. 

Therefore Starfleet Command suppressed all knowledge of the experiment and fabricated the story of a natural phenomenon occurring in the Lantaru sector which made warp travel impossible within the seven-light year radius of subspace devastated by the Omega explosion.

Protocol

Starfleet enacted the Omega Directive in response to the Lantaru incident, naming it after the last letter in the Greek alphabet, chosen to signify the molecule as the ultimate threat not only to the Federation, but to every spacefaring civilization in the entire galaxy. If a starship were to detect an Omega molecule, the following procedure would occur:

The ship's computer would disengage the engines immediately and lock out all computer access, displaying the Greek letter "Omega" on every bridge console. Only the captain would be able to disable the lockout.
 In the privacy of his or her ready room or other secured area, with the doors locked, the captain would give the computer the proper high-level security authorization code to access the sensor data.
The computer would then brief the captain regarding the detection of Omega molecules, followed by instructions to implement the Omega Directive at once – disregarding all other priorities, including the Prime Directive.
The captain, absolutely forbidden from discussing anything about what was happening with any member of the crew, would contact Starfleet Command via an encrypted channel to inform them of the situation. Starfleet Command would then dispatch a specialized team authorized to use whatever means necessary to destroy the molecules. ()

The Omega Directive was executed in the Delta Quadrant on stardate 51781.2 in 2374 by Captain Kathryn Janeway of the . On that stardate, Voyagers sensors encountered the shock wave from a nearby Omega explosion, revealing the presence of one or more Omega molecules in the vicinity. However, Voyager was out of contact with Starfleet when the detection occurred, with no specialist support to deal with the problem. Complicating the matter was the fact that Seven of Nine was aware of both the molecule's existence (due to the Borg's own Omega experiments) and the Omega Directive (the Borg having assimilated Starfleet captains, thus their knowledge).  After reconsidering Chakotay's counsel, Janeway therefore modified the protocols to their unique situation by briefing her senior staff (including Seven) on the directive, effectively enlisting the crew to destroy the molecules. The Voyager crew successfully destroyed the Omega molecules, using a harmonic resonance chamber to destroy twenty-eight percent of them and a gravimetric torpedo eliminating the rest. ()

Appendices

Background information
The first known opportunity for the Borg to have learned of the Omega Directive was in 2362, when they presumably assimilated Captain Blackwood along with the rest of the crew of the USS Tombaugh. () If Blackwood was dead before a drone could get to him, the next and most definite opportunity was when they assimilated Captain Jean-Luc Picard of the  into Locutus of Borg in 2367. ()

Apocrypha
The Omega Directive is mentioned by Captain James T. Kirk in the  video game Star Trek: Legacy after a devastating attack spreads thousands of Omega particles into a star system. Kirk asked Starfleet to develop the directive.

The game Star Trek: Armada depicts events of an Omega molecule. It was found by the Ferengi, who were preparing to sell it to the Cardassians, as they did not realize its power. The Romulans led by Sela captured it and hid it at a Romulan starbase where the Borg assimilated it. It was moved to Unimatrix 01 where an invasion force led by the Federation-Klingon-Romulan alliance destroyed it and the surrounding Borg sectors.

The Section 31 novel  details the events that lead to the creation of the Omega Directive. In it, the  forces the USS Sphinx out of warp, having been sabotaged by Section 31 in order to prevent them from revealing the research station in the Lantaru sector. This leads to an investigation that reveals Ketteract's experiment to James T. Kirk and the crew of the original Enterprise. Although Kirk tries to appeal to Ketteract to stop the experiment, he is unsuccessful and the events described in  come to fruition.

In the game Star Trek Online mission "Sphere of Influence", the player character and major characters from the Federation and Klingon sides are taken by surprise when the character Commander Winters tells everyone that "all the monitors on the bridge are showing an Omega, we're locked out of the computers and the engine's off-line" after the Enterprise-F scanned what was on the other side of the Iconian gateway near Jouret IV, thus setting the stage for the Season 8 expansion.

External link

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