The effects of travel in the Janus Vortex mirror the original transporter accident that transported James T. Kirk, Leonard McCoy, Montgomery Scott and Nyota Uhura to the mirror universe in 2267. The two universes ran parallel in terms of the fact that both versions of the Excelsior were travelling across the vortex from opposite ends. From the perspective of the crew, their ship changed to the ISS Excelsior, their uniforms had changed and a scar appeared on Captain Hikaru Sulu's face. This suggests that at some point within the anomaly, both ships exist as one, and when they separate, only brain patterns exchange places rather than physical matter. (TOS video game: Shattered Universe)
Upon arrival in the universe, Sulu quickly realised that the only way back to his universe was via the Janus Vortex that was now in Tholian space. To get there, the Excelsior had to contend with the mirror versions of Klingons, Romulans and Tholians, plus the ISS Enterprise-A under the command of Pavel Chekov, who had become increasingly suspicious of his comrade.
After a difficult journey, the Excelsior managed to switch back places with its mirror universe counterpart, that had been easily contained by Commander Pavel Chekov in command of the USS Enterprise-A. (TOS video game: Shattered Universe)
The Vortex existed in two points in space simultaneously. It existed within Federation space and was known as Janus Prime and within Tholian territory where it was called Janus Ultima. The phenomenon was known to have existed in several realities including the primary universe and the mirror universe.
|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 disruption • 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|