Tetryon

A tetryon is a subatomic particle that can only exist in subspace environments. Tetryon radiation is a bombardment of these particles. Since these particles are a property of subspace, they become highly energetic and unstable when they are extruded into normal space, which can occur by both natural and artificial means. Tetryons have a random momentum, and thus cannot be tracked by sensors.

In 2369, solanagen-based lifeforms from a tertiary subspace manifold used a stream of spatially inverted tetryons to open a spatial rupture between their native realm and the USS Enterprise-D. This allowed them to abduct several Enterprise crew members for experimentation. (TNG: "Schisms")

Intense tetryon fields, such as those surrounding the Hekaras Corridor, pose a hazard to spacecraft. (TNG: "Force of Nature")

Bombardment with tetryons can render directed-energy weapons inoperative. Jadzia Dax utilized tetryons to disable the weapons of The Albino's troops on Secarus IV in 2371. (DS9: "Blood Oath")

In 2370, Odo theorized that a weapon used by Trazko to shoot Quark was tetryon-based, to avoid activating the weapon detection scanners on the Promenade of Deep Space 9. Doctor Bashir noted that this was consistent with Quark's injuries. (DS9: "Necessary Evil")

In 2372, tetryon pulse echos were used to navigate the highly unstable atmosphere of a gas giant. However, course modifications were required after each pulse in order to avoid detection. This meant that the random momentum to avoid being tracked by sensors was invalid when emitted as a pulse. (DS9: "Starship Down")

In 2373, Harry Kim detected a tetryon surge from a Nasari ship and interpreted it as a sign they were about to attack, due to a "hunch" caused by his exposure to a Taresian retrovirus. He was later found to be right, as Nasari particle beam weapons are tetryon-based. (VOY: "Favorite Son")

Later that year, USS Voyager traveled through a region of heavy tetryon radiation. Lieutenant Tuvok enhanced the ship's shields to compensate. (VOY: "Distant Origin")

The atmosphere inside a Borg cube contains tetryon particles. (VOY: "Infinite Regress")

The weapons of Qatai's ship are tetryon-based. In 2375, Qatai used them to initiate an electrolytic reaction in a burst of antimatter ejected from Voyager's nacelles, This caused the telepathic pitcher plant to regurgitate both ships. (VOY: "Bliss")

The Nacene generate power with the use of tetryons. (VOY: "The Voyager Conspiracy")

In 2377, Voyager struck a subspace mine. This lead to the ship being flooded with tetryon radiation, and most of the crew suffering radiation poisoning as a result. With the Doctor only able to stabilize the condition of the crew at best until the radiation could be purged, Captain Janeway was forced to order the ship abandoned. Before leaving, Janeway left the Doctor, as the Emergency Command Hologram, in command of the Voyager. The Doctor was eventually able to vent the radiation. (VOY: "Workforce")

The energy barrier that isolates the territory of the Ventu on Ledos has a distinct tetryon signature. The Borg had previously encountered the technology in Species 312. The barrier left a distinct tetryon flux on debris from a Voyager shuttlecraft that crashed into it in 2377. (VOY: "Natural Law")