Nexus
The Nexus is an extra-dimensional Heaven-like realm, in which one's thoughts and desires shaped the reality around them.
Inside the Nexus, time and space have no meaning, allowing one to visit any time and any place that one could imagine.
The doorway to the Nexus is a violent, destructive temporal energy ribbon, which crosses through the galaxy every 39.1 years, among others in 2293, 2332, and 2371.
Starfleet first encountered this phenomenon in 2293, when the newly-christened USS Enterprise-B responded to a distress call from two vessels transporting El-Aurian refugees to Earth. Arriving at the vessels' location, the Enterprise found them trapped in a powerful gravimetric field emanating from the trailing edge of the energy ribbon. The Enterprise tried to transport the crew and passengers, but had difficulty maintaining a transporter lock, as the life signs were experiencing a state of temporal flux, phasing in and out of the spacetime continuum. The Enterprise was only able to save 47 out of 150 people.
- Before being rescued by the Enterprise, the El-Aurians experienced brief moments inside the Nexus, where all of their desires became reality.
Captain Kirk, a guest on the Enterprise-B's maiden voyage, was pulled into the Nexus, and for the next seventy-eight years, it was believed that Kirk had died a hero.
Desperate to get back to the Nexus, Dr. Soran, one of the El-Aurian survivors, plotted a way to get back - though it involved the destruction of two stars to do so. He launched one probe to alter the gravitational forces that influenced the course of the ribbon, and brought it to a planet he could access. From that planet, he would destroy a second star, which Captain Picard realized would destroy all of the planets in the Veridian system, including a planet with a pre-industrial population of 230 million. Picard confronted Dr. Soran on Veridian III in an attempt to stop him, but was unsuccessful in preventing him from destroying the star. As all planets in the Veridian system were destroyed, as was the Enterprise-D's saucer section, both Picard and Soran were pulled into the Nexus.
While inside, Picard located Kirk, who, from his point of view, had only just entered the Nexus. Picard initially had trouble persuading Kirk to leave the Nexus, as Kirk saw it as his opportunity to correct the mistakes of his past. Kirk soon realized, however, that the events which transpired in the Nexus were not real, and agreed to join Picard in stopping Dr. Soren. Due to the timeless nature of the Nexus, the two captains were able to leave and arrive on Veridian III at a point in time before Soran destroyed the star. Teaming up to fight him, they were successful in changing history and stopping Soran, but unfortunately Kirk was killed in the process.
