History:
In 2371, Cardassian scientists and Deep Space 9 personnel collaborated to test a subspace relay that would provide communications between tha Alpa and Gamma Quadrants through the Bajoran wormhole. Serendipitously, during the test, a comet near the wormhole broke up, leaving behind a trail of silithium particles in the wormhole. These particles created a subspace filament that facilitated the propagation of radio signals across the wormhole.
DS9 "Destiny" ; Star Trek Encyclopedia II
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