Appendix 4 - Travel =================== This appendix is about travel and its many forms, both on the Interstellar level and on or close to the planetary surface. It concentrates mainly on the forms of travel employed by the Imperium of Mankind. It also discusses time travel in the WH40K universe. A4.1 Interstellar Travel =-=-=-=-=-=-=-=-=-=-=-=-= The Imperium of Mankind is spread across almost the entire Galaxy and consists of more than a million worlds. Although this is a huge number of planets it is nothing when compared to the immense size of the Galaxy. The Imperium is actually spread very thinly across space: its worlds are dotted through the void and divided by hundreds, if not thousands, of light years. It is therefore wrong to think of the Imperium in terms of a territory which extends across the Galaxy. The truth is far more complex. Within the Galaxy are countless alien civilisations, many separate Ork empires, and vast areas occupied by the Tyranids or given over to Chaos. Most of the Galaxy remains unexplored. Who knows what secrets lie undiscovered amongst the stars? Undoubtedly there are other advanced civilisations, lost human colonies, and the ruins of long dead races waiting to be explored. The pattern of human settlement across the Galaxy undoubtedly owes much to the nature of space travel. All interstellar travel is undertaken using power warp drives, also simply called Warp drives, which launch a spacecraft into the alternative dimension of reality called many names, the most common being Warpspace, the Warp, the Void, the Empyrean Realm, the Immaterium or the Realm of Chaos. Within the Warp a ship can cover the equivalent of many thousands of Light Years within a relatively short time, from a few days or weeks to a few months, before dropping back into "real" space far away from its starting point. Warpspace is an alternate dimension composed of energy as opposed to the physical space of the material universe. There are dangers within the Warp which can wreck spacecraft and carry them off course, unexpected turbulence, Warp storms, and loops that can trap a ship for eternity. Because of the unpredictable and turbulent nature of Warpspace, some parts of the Galaxy are harder to reach than others. Some zones are eternally isolated by violent currents of movement within Warpspace. Other areas are difficult to get to or can only be reached during periodic lulls in the Warp. More bizarre still, some parts of Warpspace act like power vortices, pulling or sucking helpless spacecraft to their doom. Only the spacecraft of the Imperium can fully exploit the medium of Warpspace to travel from one side of the Galaxy to another. Other races, such as Orks, can only travel short distances through the Warp and this limits the size of their individual empires and prevents them becoming united. The Eldar, the other known advanced race you might expect to have a good understanding and technology of Warp enabled craft, cannot do so because of a dangerous enemy of the Eldar race that lurks in the Warp, only too ready to consume any lost Eldar souls. It is only this factor, the fact only Mankind can fully exploit the Warp to its full potential, which enables the Imperium to function as a whole. The reason why the spacecraft of the Imperium can move quickly over the entire Galaxy, while other races suffer more restricted and slower spaceflight, is a combination of three factors. The first is the maintenance of ancient technology by the Adeptus Mechanicus - the Tech Priests of Mars who preserve the lore of ancient science on behalf of the Adeptus Terra. Without the technological advantage of efficient Warp drive engines, it would be impossible for the Imperium to defend its scattered planets. The second factor is the existence of human mutants known as Navigators - a race apart which traces its origins to the Dark Age of Technology. Only a Navigator can pilot a ship within Warpspace. His swollen cranium houses a third eye, called the Witch Eye by some, that allows him to see the currents of the Warp, and enables him to guide his ship through Warpspace to its eventual destination. Other races must rely upon guesswork and endless corrective manouvres to travel even short distances through the Warp. The third factor which makes Warp travel possible is the immeasurably powerful psychic beacon called the Astronomican (not to be confused with the Necronomican in the game Call of Cthulhu!). Broadcast by a choir of psykers from Earth, the Astronomican reaches out through Warpspace, guiding spacecraft to their destination. Only a Navigator can sense the guiding light of the Astronomican in the shifting currents of the Warp, and only he can follow its psychic signal. It is the Astronomican which allows a Navigator to use his powers to the full: without it not even the most powerful Navigator could reliably pilot his ship to its destination over the immense distances which separate the worlds of the Imperium. Perhaps most dangerous in travelling through Warpspace is the ever present threat of running into a sudden Warpstorm. Navigators are versed in spotting the signs of a coming Warpstorm and navigating round it if possible, even so thousands have been killed, engulfed in a sudden Warpstorm that literally tore apart their ship. More information on Navigators and their abilities can be found in the chapter on Psionics. One limitation on Warp travel is that a spacecraft cannot go into the Warp while within the atmosphere or gravitional influence of a planet. Craft use sub-light propulsion systems to go into planetary orbit before engaging Warp engines. A similar limitation applies on leaving Warp within range of a large gravitational influence. Actually, its not such much you *can't* do these things, more highly not recommended, and potentially very dangerous for all on board. A4.2 Surface Travel =-=-=-=-=-=-=-=-=-=- Surface travel, the action of travelling from A to B within the gravitational sphere or atmosphere or a planet, takes a variety of forms, depending on who is doing the traveling and how technologically advanced the culture of the planet is. Many primitive or medieval worlds still rely on horses or other native beasts of burden, and employ sailing ships to traverse the oceans of their world. More advanced cultures employ automobiles drawing on a wide variety of power sources, from hydrocarbon fuels to hydrogen power cells to plutonium mini-reactors. These automobiles themselves take a variety of guises. Common families of close surface vehicles are: * Land vehicles - such as our present day cars, buses, motorcycles, quads, etc. * Jet craft - airborne vehicles that generally travel close the ground, propelled by rear jets. A common example of this class of craft is the Eldar Jetbike. * Skimmers - often similar to land vehicles in style and design (the shape of the vehicle, driver position, etc.) but incorporating anti-gravity generators to hover close to the ground. They have a limited ability to travel higher, though this consumes more power and is avoided. This class of craft is also referred to sometimes as Hoverers. * Sea-borne craft - anything that travels physically through the waves. Craft that travel over the oceans without touching the water surface are generally classed as varieties of Skimmer. * Walkers - relatively rare machines whose propulsion mechanism is based on a bipedal or quadropedal walking motion. Most famous for this class of transport is the Eldar. The Squats employ similar engineering principles. After skimmers, walker based vehicles with heavy "feet" and sophisticated suspension and balance systems are best able to navigate the frequent mudslides on many Squat homeworlds. For travel higher off the surface, such as atmospheric travel, again a wide range of transport is used. Some reasonably advanced worlds, whose technology has not yet made available routine space travel (such as real world Earth) employ craft designed to travel in the atmosphere, but whose intention is not to leave the atmosphere, merely to carry passengers from A to B on the planets surface. More advanced worlds for whom interstellar travel is somewhat commercialised may use craft designed to allow either surface to surface travel, or surface to orbit. this is the sole purpose of some craft, to ferry people from surface to orbit or vice versa. Many large space capable craft maintain a fleet of such craft for transport to and from the planetary surface. Warp capable craft routinely employ sub-light travel within planetary atmospheres, or keep a number of smaller craft for travelling planetside once in planetary orbit. A4.3 Time Travel =-=-=-=-=-=-=-=-= In the WH40K universe, the existance of Warpspace brings intriging possibilities for time travel. The potential for time paradoxes is in itself par for the course where Chaos is involved - and I can't think of anything that would fit the nature of Chaos *better* than an impossible time paradox. Chaos being Chaos, the effects will vary from case to case. There are precedents in the published WH40K material for odd time effects caused by Chaos and the Warp. There is the dilated time that allows the same Chaos Space marines who first rebelled against the Imperium millennia ago to still live today in the Eye of Terror. There is the Eldar codex, which states that there exist in the Webway paths that lead to the past and future, and the Webway is - we presume - part of the Warp. Then there is the Dark Angels codex, which tells us that on being sucked from the surface of Caliban into the Warp, the fallen Dark Angels were spread throughout both *time* and space. Time travel by means of the effects of Chaos should happen for the most part at unpredictable times and by unintentional means. There are, however, many possibilities for deliberate time travel. Consider the already mentioned Eldar Webway, which contains paths to the past and future. These paths will be rarely travelled and very dangerous to take, assuming a character is allowed by the Eldar to enter the Webway at all. Even among the Eldar Harlequins, masters of the Webway, few know the secrets of these paths. Few will know their locations or precisely where (or when) they lead. Probably only the oldest Eldar Harlequins will know this, mostly likely the Great Harlequins, or the mysterious Solitaires. Consider also that ships can be thrown off course in the Warp and sent, usually unintentionally or by the whim of Chaos, into the past or future. Just occasionally, such a current in the Warp might become temporarily stable, possibly allowing another ship to follow in a lost ships' wake, or even allowing the lost ship to return if its Navigator can successfully re-trace its movements in the Warp. Such paths through time in the Warp should never be relied upon, however. Finally, psykers have been known to be able to open portals to Warpspace. Some powerful psykers (few of them Imperially sanctioned!) can even open tunnels through the Warp, portals from one place, passing briefly through condensed Warpspace, to another place far away on the other side of the portal. Who is to say that such tunnels or portals could not go to the past - or future? Perhaps an ancient alien or Chaotic artefact could mimic similar abilities. Psykers and Navigators have also been known to have seen glimpses of the past and future when gazing into the Warp, visions of other times and places. Some have been said to have witnessed their own death. Some never recover, and either spend the rest of their days in asylums, or sent (mercifully, so some would say) to be consumed by the Emperor to sustain his spirit. The effects of time paradoxes are undefined, and could take many many forms. Suppose a man caught in a Warpstorm was blasted back into the past, where he ended up causing the death of his great, great grandmother. There are many theories of time travel across the Imperium (many of them deemed Heretical by the Inquisition). Some say the cosmos would somehow intervene to prevent the act, thereby preventing the paradox - perhaps the man slips, or causes a non-critical injury leaving her for dead. Perhaps it might, but this could not be relied on every time. More likely if Chaos is involved, is an impossible paradox. If the grandmother dies, then whether or not the man blinks out of existence a result, a paradox remains. If the grandmother was killed, how was the man born; yet if the man was never born, who killed the grandmother? Perhaps the future might be effected, perhaps it wouldn't. Who can say, where Chaos has a hand? Other theories of time paradoxes exist, including that of the Observer Effect (which approximately states that the future is only changed by changes in the past if those of the future - future observers - become aware of it). Many such theories remain unproven or unprovable, however, due to the unpredictable nature of time travel as influenced by Chaos. Some postulate that time travel would become impossible were Chaos banished forever, other believe that it would still be possible, but become more predictable and dependable. The likelihood of Chaos being banished remain remote, however, and the answer will likely never be known. The reader is suggested to read "GURPS: Time Travel" for ideas and further thoughts on the nature and resolution of time paradoxes.