In the fictional universe of Star Trek, a spatial anomaly is a very broad term for any sort of extraordinary disruption in the space-time continuum. Often, they can take the form of irregularities in gravity, ripples in space that can damage equipment and personnel, alterations in the laws of physics, and areas of disruption inimincal to the human brain.
The Delphic Expanse is rife with such distortions, generated by spheres to reconfigure space to resemble the Sphere Builders' transdimensional realm. The Triannons referred to the anomalies as "the breath of the Makers ."
The USS Enterprise-D once encountered a spatial anomaly, which turned out to be a multiphasic temporal convergionce in the spacetime continuum, caused by an eruption of anti-time . (TNG: "All Good Things...")
Another was encountered by the USS Voyager in the Delta Quadrant, and turned out to be a graviton ellipse : an extremely rare spatial anomaly that travels through subspace, emerging into normal space occasionally and without warning. (VGR: "One Small Step ")
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