- "It was like being inside joy. As if joy were something tangible and you could wrap yourself up in it like a blanket."
- —Guinan, 2371 [src]
The Nexus is a nonlinear temporal phenomenon which can be entered via a temporal flux energy ribbon which crosses the Galaxy every 39 years. It is possible that the ribbon was created by a young Q billions of years ago. (TNG novel: Q-Space)
First known contact with the Nexus was made in 2293 by a group of El-Aurian refugees, including Guinan and Tolian Soran. The refugees were rescued by the USS Enterprise-B, but at the apparent cost of the life of James T. Kirk. (TNG movie: Star Trek Generations)
In 2332, Guinan was visiting Oblivion when the Nexus energy ribbon again crossed through the Galaxy. She felt it even 3,000 kilometers from the orbital city, reopening old wounds for her. (STA novel: Oblivion)
While exploring the Rotanev system, the USS Forrestal disappeared in the Nexus. The ship and its crew were taken over by Khaj'Buur, who hoped to use the Forrestal to escape from the Nexus and reap revenge on his imprisoners, and the ship remained unseen for the next 78 years. (STO - Escalation mission: “Beyond the Nexus”)
In 2371, Soran, having become obsessed with returning to the Nexus, committed several criminal acts in an attempt to bring the Nexus to Veridian III, having determined there was no guaranteed safe way to approach it by ship. Soran was defeated by Captain Jean-Luc Picard and Kirk, although doing so cost Kirk his life. (TNG movie: Star Trek Generations)
In 2384 the Nexus re-entered Federation space. It was posited that the result of Soran's attempts to alter the course of the Nexus was that its 39 year cycle had been permanently disrupted. A team of Federation scientists were able to use the Nexus's own energies to construct an energy bubble around the Nexus in order to prevent access by individuals who would seek to use the ribbon to alter the timeline. (TNG novella: The Stuff of Dreams)
In 2410, the USS Madison was investigating the reappearance of the Forrestal when crewmembers from that ship beamed aboard and took control. Khaj'Buur took over the minds of most of the crew, but a few officers on the Madison managed to escape from his mental powers.
When the USS Challenger arrived to investigate shortly after, the commandeered Madison opened fire on her. Captain Geordi La Forge beamed over to examine the incident, and made contact with Commander T'Fai. Now aware that an alien was responsible for the attack and the loss of the Forrestal, La Forge traveled through the ship and engaged Khaj'Buur on the Madison's bridge. On the verge of defeat, Khaj'Buur escaped to the Forrestal and continued his assault from there. Captain La Forge returned to the Challenger and returned fire. Khaj'Buur, out of options, surrendered to Captain La Forge and was taken into Starfleet custody. (STO - Escalation mission: "Beyond the Nexus")
In one alternate timeline, Montgomery Scott traveled from 2370 to 2293 to beam Kirk from the Enterprise-B just before he was pulled into the Nexus. This altered history so that the Borg invasion of 2063 Earth was successful; without Kirk's aid, Picard either failed to stop Soran or died in the attempt, and Earth was thus conquered before humanity could develop Starfleet. Fortunately, the Enterprise-D had followed Scott on his journey to the past and were thus protected from the changes in history that had occurred while they were 'in transit'. On the advice of Guinan and the Guardian of Forever, the Enterprise was thus able to send Kirk into the Nexus moments before they were destroyed by a Borg cube, undoing Scott's original rescue of him and restoring history to its proper course. (TNG novel: Engines of Destiny)
|space weather||cosmic storm • distortion ring • gaseous anomaly (Herbig-Haro formation) • ion storm • magnetic storm • maelstrom • meteor shower • particle fountain • plasma storm • solar storm • spatial implosion • star-node • tachyon eddy • Thraz Streamer • wave nexus|
|gravitational anomalies||gravimetric distortion • gravimetric eddy • gravimetric interference • graviton ellipse|
|subspace anomalies||subspace compression anomaly • subspace distortion • subspace fissure • subspace fracture • subspace granulation • subspace gravity inversion • subspace gravity spike • subspace tunnel|
|temporal anomalies||Kerr loop • multiphasic temporal convergence • Nexus • temporal distortion • temporal gate • temporal rift • temporal vortex • Tipler cylinder • toroidal continuum fold|
|rifts and ruptures||dimensional gate • interphase • Janus Vortex • spatial distortion field • space-time fracture • spatial rift (spacial flexure) • subspace rupture • Tyken's Rift • warp-gate|