Bajoran Wormhole
In the fictional Star Trek universe, the Bajoran wormhole is a spatial anomaly located near the planet Bajor which the Bajoran religion refers to as the "Celestial Temple". It appears as an aperture of swirling golden light surrounded by blue clouds, which appears when a vessel approaches or exits from it and disappears when a vessel enters it. The wormhole can only be traversed by ships traveling at impulse (sub-light speed) velocities.
The wormhole is discovered in the first episode of Star Trek: Deep Space Nine. It is found to lead from the Bajor-B'Hava'el system in the Alpha Quadrant to the Idran system in the Gamma Quadrant, seventy thousand light-years away and on the other side of the galaxy. Due to the strategic importance of such a phenomenon, the Deep Space Nine space station is moved out of Bajor's orbit and repositioned near the wormhole.
Starfleet Commander Benjamin Sisko and Lieutenant Jadzia Dax are the first to make contact with the wormhole and its creators, incorporeal beings known as the Prophets in Bajoran religion; they are simply referred to as "Wormhole Aliens" by the Federation. It is they who provided the Orb-like energy artifacts (or "Tears of the Prophets") to the Bajorans and these artifacts are the basis of Bajoran religion. The wormhole closes at one point, as a result of one of the Tears of the Prophets being temporarily rendered inert by the Pah Wraiths. It is later restored by the discovery of an additional orb by Benjamin Sisko.
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