Multiple realities
(covers information from several alternate timelines)
![Temporal wake](https://cdn.statically.io/img/static.wikia.nocookie.net/memoryalpha/images/3/3a/Temporal_wake.jpg/revision/latest/scale-to-width-down/180?cb=20101014192417&path-prefix=en)
The Enterprise caught in a temporal wake
A temporal wake is an energetic phenomenon that can be created as a byproduct of a temporal vortex, insulating anything caught inside from an alteration of the timeline.
In 2373, a Borg sphere generated a temporal vortex to the year 2063, where they changed history by stopping Zefram Cochrane's first warp flight, and assimilating Humanity. Having become caught in the vortex's wake, the USS Enterprise-E remained unaffected by the alteration to history, allowing the crew to follow the sphere through the vortex and able to not only restore but instigate the original timeline. (Star Trek: First Contact)