Star Trek: Everything We NOW Know About The 25th Century

In 2382, the USS Anaximander travelled through several realities, attempting to close rifts that were causing damage to the fabric of space and time. They were largely successful, channelling all of that energy into one final place. As long as the crew there could deal with the issue, everything would come out ok.

Cue Lt. Junior Grade Bradward Boimler screaming that everyone was going to die. Classic Boims.

The events of Fissure Quest and The New Next Generation led to the creation of the first stable mutiversal subspace rift, allowing ships like the Anaximander to travel from one reality to another. Though this has yet to be revisited on-screen, the possibilities here are endless.

The Romulan supernova of the mid-2380s may never have occurred in another reality, thus offering the Romulans plenty of reason to explore. The Borg may seem to be entirely wiped out (bar Juratti's collective) in 2401, but is that the case everywhere? 

With Starbase 80 in place and (barely) functional, the mission is clear. If Starfleet's mission has always been to seek out new life and new civilisations, it's clear that the exploration of this new rift is very much a part of that mission. There is also the small matter of the synthetic creatures that promised to wipe out all organic life, those same creatures who peeked their tentacles through yet another rift in Et In Arcadia Ego, Part 2. Perhaps someone should use this rift to check up on that. 

Soon.