The Enterprise at a subspace fold
Scan data for a subspace fold
A subspace fissure or subspace fold was a type of subspace anomaly that affected normal space.
In 2259, the USS Enterprise discovered a naturally-occurring subspace fold in the outer reaches of the Alpha Quadrant, at coordinates 2733.5558. The phenomenon had an aperture of 3.02×10-8 by 5.2×10-10 light years, and emitted gravitational radiation of 9.353x10-16 joules. It had a rate of refraction of 0.01 g/s, a spacetime distortion of 1.457×10-14, a positive obscuration, and no detectable electromagnetic emissions.
The fold held promise for increasing the speed of subspace communication in the sector, as frequencies propagated within it three times faster than normal. Since transmitting conventional messages into the fold had yielded no results, the crew tried sending a song. This created a resonant frequency that dislodged a quantum uncertainty field from the fold. The result was a region of altered reality within which people were forced to sing and dance during moments of heightened emotion, accompanied by audible music, as though they were in a musical.
The Enterprise had become tethered to the uncertainty field, precluding escape. The crew attempted to seal it by connecting shield harmonics and the Heisenberg compensator to the deflector array and firing a beam into the fold, but this was unsuccessful. The field subsequently expanded across the subspace relay network to the entire Federation fleet as well as parts of the Klingon Empire. A Klingon battle cruiser commanded by General Garkog was affected, and diverted toward the fold with the intent of destroying it.
Experiments on subatomic particles from the fold revealed that firing on it with photon torpedoes would destroy everything affected by the uncertainty field, thus necessitating a solution before the Klingons' arrival. Ensign Nyota Uhura determined that a quantum improbability spike of 344 gigaelectronvolts would shatter the fold. By rallying the Enterprise crew to sing together in a "grand finale", she was able to achieve such a spike and collapse the fold before the Klingons, who Pike conned into aiding them, could open fire. (SNW: "Subspace Rhapsody")
In 3189, Cleveland Booker took his ship into the Verubin Nebula to navigate the radiation hazards that the USS Discovery was too large to navigate. He was able to get his ship to a subspace fissure in the nebula, which allowed him the clearance to complete scans of the crash site of the KSF Khi'eth on a planetoid. (DIS: "Su'Kal")