Editing Stargate (device) (section)

===Wormhole===
[[Image:Kawoosh side.jpg|thumb|right|Side-on view of a stargate as an unstable vortex is ejected]]
Once an address is dialed, the gate is said to have created a "stable [[wormhole]]" between itself and the gate dialed. The creation process is depicted with great consistency, and hence has become one of the defining [[Motif (art)|motif]]s of ''Stargate'', at times being central in both the ''SG-1'' and ''Atlantis'' title sequences. It involves the generation of the "puddle of water" portal that lasts roughly two seconds, and is completed by the ejection of an unstable energy vortex resembling a surge of water or [[mercury (element)|quicksilver]]. The vortex is portrayed as a symbol of the stargate's power, invariably causing characters to become affected by [[awe]].<ref name="The Scourge">{{cite episode|title=The Scourge|episode-link=The Scourge (Stargate SG-1)|series=Stargate SG-1|series-link=Stargate SG-1}}</ref> Any matter that comes into contact with the vortex is annihilated on a molecular level, as is dramatically demonstrated by a pair of smoking shoes in the episode "[[Prisoners (Stargate SG-1)|Prisoners]]".<ref name="Prisoners">{{cite episode|title=Prisoners|episode-link=Prisoners (Stargate SG-1)|series=Stargate SG-1|series-link=Stargate SG-1}}</ref> In season 9's "[[Crusade (Stargate SG-1)|Crusade]]", the unstable vortex was [[Onomatopoeia|onomatopoeidiacally]] referred to by Col. Carter as the "Kawoosh", emulating the sound of the initial vortex. This aspect has been used in some cases to dispose of highly hazardous materials. The vortex is also used on one occasion to dispose of a body in a formal funeral service – the body was placed on a pyre in front of the gate, which was then activated.

The actual portal of a Stargate appears inside the inner ring when an address is correctly dialed. This has the appearance of a vertical [[puddle]] of water, which represents the "event horizon" in the show. In non-fictional parlance, an [[event horizon]] is the perimeter around a [[black hole]] or wormhole beyond which the gravitational pull of the singularity would be too strong to overcome. The wavering undulations characteristic of water are supposed to represent the "fluctuations in the event horizon".<ref name="Children of the Gods">{{cite episode|title=Children of the Gods|episode-link=Children of the Gods|series=Stargate SG-1|series-link=Stargate SG-1}}</ref> This puddle may then be entered (usually accompanied by a watery squishing sound), and the traveler will emerge from a similar pool at the destination Stargate.

The show makes it clear that transit is strictly one-way; an attempt to travel "backwards" causes the traveler to be destroyed.<ref name="A Hundred Days">{{cite episode|title=A Hundred Days|episode-link=A Hundred Days (Stargate SG-1)|series=Stargate SG-1|series-link=Stargate SG-1}}</ref> Although in the first episode the Goa'uld who come through at the beginning appear to walk back through the event horizon after taking a hostage, in actuality they dialed out again using a hand-held device, as the whooshing sound is audible in the background.<ref name="Children of the Gods" /> As matter is only transmitted through a Stargate once the whole object has passed the event horizon, a person or object could be retrieved from the event horizon before entering completely, as the Stargate would automatically reintegrate the traveler.

[[Image:Wormhole Travel Stargate Movie.jpg|thumb|Original wormhole travel from the [[Stargate (film)|''Stargate'']] movie and ''[[SG-1]]'' seasons 1-8]]
Passage through a Stargate's wormhole is depicted as a visual effect of shooting through a tunnel in space. The average travel time between Stargates is 3.2 seconds.<ref name="Insiders">{{cite episode|title=Insiders|episode-link=Insiders (Stargate SG-1)|series=Stargate SG-1|series-link=Stargate SG-1}}</ref> In the movie and early ''SG-1'' episodes, travelers exit from the Stargate covered in frost and at high speed (often being knocked from their feet), feeling as though they have been on a "roller coaster ride". The character Major [[Charles Kawalsky]] describes Stargate travel as worse than "pulling out of a simulated bombing run in an [[F-16 Fighting Falcon|F-16]] at [[g-force|eight-plus ''g'']]", with Major [[Louis Ferretti]] adding that on the other side one is "frozen stiff like having just been through a blizzard naked".<ref name="Children of the Gods" /> In later episodes the experience is no different from stepping through a door,<ref name="Shades of Grey">{{cite episode|title=Shades of Grey|episode-link=Shades of Grey (Stargate SG-1)|series=Stargate SG-1|series-link=Stargate SG-1}}</ref> explained as a result of refinements made to the dialing computer at the [[Stargate Command|SGC]].

Under normal circumstances, a wormhole can only be maintained for slightly more than 38 minutes.<ref name="Thirty-Eight Minutes">{{cite episode|title=Thirty-Eight Minutes|episode-link=Thirty-Eight Minutes (Stargate Atlantis)|series=Stargate Atlantis|series-link=Stargate Atlantis}}</ref> Extending the wormhole duration beyond that requires tremendous amounts of power, such as that provided by a nearby [[black hole]].<ref name=AMatterofTime>{{Cite episode|title=A Matter of Time|episode-link=Stargate SG-1 season 2|series=Stargate SG-1|series-link=Stargate SG-1|airdate=1999-01-29|season=2}}</ref><ref name="First Strike">{{cite episode|title=First Strike|episode-link=First Strike (Stargate Atlantis)|series=Stargate Atlantis|series-link=Stargate Atlantis}}</ref>

While the "kawoosh" effect in the movie was created by filming the actual swirl of water in a glass tube, and looked like a vortex on the back of the Gate,<ref>DVD commentary for the ''Stargate'' film</ref> on the TV series, this effect was completely created in [[Computer graphics|CG]] by the Canadian [[visual effects]] company [[Rainmaker Digital Effects|Rainmaker]]''.''<ref>''Stargate Magic: Inside The Lab.'' Special feature on [[Stargate SG-1 DVD]] Volume 37 (Lost City).</ref> At the beginning of Season 9, the original movie wormhole sequence was substituted by a new sequence similar to the one already used on ''Stargate Atlantis'' but tinted bright blue (whereas in ''Atlantis'' it is green).<ref>Audio commentary for "The Ties That Bind", SG-1.</ref> ''Stargate Universe'' uses a darker shade of blue.

Throughout the run of the television franchise, it cost $5,000 to show a person stepping through the event horizon, using visual effects.<ref>Audio commentary for ''[[Stargate: Continuum]]''</ref>