Dimensional Disturbance

The … never made it all the way to … to study the anomalies surrounding it. The ship, along with Science Officer … and crew, blinked out of existence as it was navigating the debris field.

And then reappeared minutes later.

… reports that they found themselves, briefly, in some extra-dimensional space. External viewports revealed that they were surrounded by countless ships of alien design, suspended in a seemingly endless void. Before the crew could get their bearings, the vision abruptly faded and they found themselves back in regular space.

However, roughly half of the crew are missing - Science Officer … speculates that they may have been selectively trapped, by some unknowable mechanism, in that strange space.

As the … passed through the asteroid belt on its way to …, Science Officer … reported that the ship experienced a number of sudden gravitational shifts. Ever curious, … dispatched a number of probes to scan the debris field to discern the cause.

It turns out that the culprit is a number of gravity generators of old, alien make. Sputtering on dying energy sources and with their polarities inverted, they occasionally spew reverse-gravity into the void, though not with enough force to cause any serious harm. Not anymore.

Science Officer … theorizes that the generators once provided artificial gravity for a large asteroid in the belt, but some malfunction eventually tore the rock apart.