Tylium (pronounced "TILL-lee-um") is a material used to fuel the propulsion systems of Colonial and Cylon spacecraft. At least three forms exist: tylium ore, refined tylium precursor, and refined tylium (the fuel itself).
Typically, tylium ore is mined from asteroids and is apparently not found on the Twelve Colonies natively. Large tylium ore deposits can keep fleets fueled for years (TRS: "The Hand of God"). In its raw form, tylium is a relatively fine, powdery substance that is liquefied and refined by refinery ships. Care needs to be taken to not introduce impurities into the fuel, which can cause engine malfunctions (TRS: "Dirty Hands").
According to Dr. Gaius Baltar, tylium has the following characteristics:
- Tylium ore is rendered inert and unusable when exposed to nuclear radiation;
- Refined tylium precursor is more unstable and much easier to ignite than the finished fuel itself;
- Refined tylium has a tremendous enthalpy to the order of approximately half a million gigajoules per kilogram, or about 6 times greater than uranium-235 and 81% that of deuterium fusion;
- A tylium detonation results in no radioactive fallout (TRS: "The Hand of God")
Pure tylium can be easily detonated by a conventional warhead. Moreover, igniting fuel lines on spaceships usually quickly result in their loss (TRS: "Miniseries, Night 1"). The fuel can also be used to construct improvised mines (TRS: "The Eye of Jupiter").
Tylium (pronounced "TIE-lee-um") is an unstable mineral element used as fuel by both the Colonial and Cylon forces in the Seventh Millennium. The substance is often mined and it can explode when energy, such as discharges from laser pistols, impact its natural form.
Following the Battle of Cimtar, the Fleet heads to the planet Carillon, believing it to have tylium based on a report from an old mining expedition. Much to the surprise and shock of many, Carillon is discovered to have tylium in mass quantities, so much so that when the Colonials ignite the tylium with their energy weapons during a pitched battle with Cylon forces, the planet is destroyed in a cataclysm (TOS: "Saga of a Star World").
The Colonials make use of a separate fuel source, solium, for fueling various ships from Vipers to freighters, like Gemini (TOS: "Saga of a Star World", "Fire in Space"). This implies that tylium may well be the raw mineral from which other grades of fuel are derived, in the same way that diesel and gasoline are petroleum derivatives.
In the separate continuity
Tylium is mentioned in the following separate continuity tie-ins, notably:
- Deathtrap!, which adapts the third part of Original Series' "Saga of a Star World".
- Battlestar Galactica Annual 2014, where Baltar's backstory is relayed, in addition to his discovery of Carillon.
- Enthalpy describes the thermodynamic potential of a system (H), and its simplest definition is the sum of the system's internal energy (U), and the product of its pressure (p) and volume (V): H = U + pV.
- The official series web page on the Sci-Fi Channel web site incorrectly spells the substance as "tyllium" in the description of the mining ship on the ships page. As the Original Series DVD material, as well as labels seen in "Dirty Hands", show the spelling as "tylium," Battlestar Wiki contributors should use "tylium" as the correct spelling.
- The first usage of this term uses the "TIE-lee-um" pronunciation (q.v. Original Series' "Saga of a Star World") as opposed to subsequent uses of "TILL-lee-um" (q.v. Re-imagined Series' "Miniseries").