The Omega 4 relay is surrounded by hazard beacons and automated warnings. Over the last thousand years, many ships have attempted to pass through it, but none have returned. The only ones to pass freely back and forth through the relay are the mysterious Collectors.
There are many theories why ships never return from Omega 4. Some say there is a black hole at the far end; others (mostly the impoverished underclass of Omega) believe there is some form of earthly paradise. Most, however, simply think the Collectors capture or destroy those passing through the relay.