View source for Artificial gravity

{{Status|Canon}}
'''Artificial gravity''', also known as '''contragravity'''<ref name="WF86">''[[Halo: Warfleet – An Illustrated Guide to the Spacecraft of Halo|Halo: Warfleet]]'', Weapon-Ships - p.82-83</ref>, is employed by the [[United Nations Space Command|UNSC]], [[Covenant]] and the [[Forerunner]]s, to generate gravity of varying strengths in an otherwise zero or low-gravity environment.<ref>[[Wikipedia:Artificial gravity#Centrifugal Force|'''Wikipedia''': Artificial Gravity'']]</ref> 

==Centrifugal force==
A number of UNSC ships employ rotating sections of the hull to provide centrifugal force on the interior of the hull to allow comfortable movement in "gravity." On certain ships, the rate of rotation can be adjusted, allowing more or less gravity, and a number of other ship classes, such as {{Class|Halcyon|light cruiser}}s, also used rotating sections before the introduction of more advanced gravity plating.{{Ref/Note|Realistically, the rate of spin for many of the smaller UNSC ships would have to be quite low (2 RPMs or lower) to prevent the crew from getting dizzy and nauseated due to the Coriolis effect. This means that the "gravity" produced by the rotating sections of most UNSC ships would be well below 1g. Space stations and colonies at least a mile in diameter would likely be able to produce 1g. However, even the relatively small rotating section that constitutes the gym of the carrier ''Atlas'' is said to be able to simulate gravity up to 2g without causing nausea. Although this could be a simple oversight, it is possible that the nauseating effects of spin are mitigated through unknown means, possibly by using anti-gravity emitters in tandem with the rotating carousel system. This style of artificial gravity also fails to explain how an [[elevator]] can run through and traverse out of the rotating sections, something that occurs multiple times in the novels.}}

The [[Halo Array|Halo installations]] rotate by means of an artificially-induced gravity field,<ref>'''[[Halo: The Flood]]''', ''pages 13-14''</ref>, but do not use this rotation to provide any form of artificial gravity, instead relying wholly on gravitic-generators to keep objects rooted to their surface.<ref name="lorestream">[https://www.youtube.com/watch?v=fYaxRoAf96s ''YouTube:'' Halo Lore Stream: The Halo Array]</ref>

==Non-centrifuge artificial gravity devices==
The study of application of [[gravitics]] involves the process of manipulating gravitational forces. It is used for weaponry, propulsion and other technologies.

===Covenant===
Almost all Covenant vessels employ some sort of artificial gravity mechanism that does not involve rotating hull sections or acceleration. Instead, their method allows for the generation of actual gravity.{{Ref/Note|It has been speculated that the Covenant may use [[Wikipedia:Diamagnetism|diamagnetism]], but this is very unlikely: though there would be no known adverse health effects, it would mean that the entire ship would have to be made of non-magnetic materials, have heavily shielded electronic equipment and the crew would not be able to use anything made of metal. The use of ultra-dense materials which generate their own gravity has been suggested, but this would make the ship incredibly heavy and massive. Considering the UNSC still use some form of reaction/rocket propulsion, it seems rather unlikely that this would be the case.}}

The most likely explanation is that the Covenant have developed some form of directional gravity emitter that generates a beam of gravitons. This would mean the Covenant are able to generate gravity without mass. It is possible that the Covenant have figured out a way to convert energy into graviton particles and direct them in much the same way as a beam of light; this seems to be the basis for the Covenant's [[gravity lift]]. The production of "antigravitons" would create a repulsive effect, which may be the basis for their [[boosted gravity propulsion drive]] and [[repulsor engine]]s. All this suggests the Covenant are able to produce gravity and antigravity as easily as humans can produce positive and negative electric current.

===Human===
While some human ships used rotating centrifuges to mimic gravity, humans did possess a form of artificial gravity even prior to their contact with the Covenant. This is demonstrated by the [[UNSC Department of Commercial Shipping|DCS]] [[DCS light freighter|freighters]] enabling artificial gravity through "anti-gravity units" and the orbital platform ''[[Tiara]]'' having artificial gravity without the use of rotating sections.<ref>'''[[Halo: Contact Harvest]]''', ''page 68''</ref><ref>'''Halo: Contact Harvest''', ''page 125''</ref> Additionally, many ship classes commissioned before the Human-Covenant War, including [[Halcyon-class cruiser|''Halcyon''-class cruisers]] and [[Phoenix-class colony ship|''Phoenix''-class colony ships]] were known to have a form of artificial gravity other than spinning sections. Typically, artificial gravity systems are found on older craft, because newer craft rely on the more effective and, ironically, lower-tech rotating carousel system.<ref name="Ency">'''[[Halo Encyclopedia (2009 edition)]]''', ''page 211''</ref>

Artificial gravity systems consume power at a tremendous rate, so much so that a ship's [[fusion reactor]]s typically cannot keep them running for more than a day and often far less if the ship is in combat or expending energy on maneuvers.{{Ref/Reuse|Ency}} As a result, during routine operations, rotating carousel sections spin to generate gravity. In combat or crisis situations, the carousels are locked in place and artificial gravity systems are activated. Some Captains eschew artificial gravity altogether. Using the technology allows high-gravity maneuvers which would otherwise put stress on the crew. This allows combat teams to focus on battle rather than the uncomfortable conditions aboard the ship. However, many naval technicians maintain that the technology wastes too much energy in extended combat.{{Ref/Reuse|Ency}}

It may be that [[antigravity plate]]s were related to tests with artificial gravity. Since the antigrav plate had a crushing or repulsive effect, and it was described as generating a beam, it most likely generated directed antigravitons.<ref>'''[[Halo: Ghosts of Onyx]]'''</ref>

UNSC starships clearly have a form of [[anti-gravity technology]], demonstrated by their ability to hover in planetary atmosphere without rocket propulsion being directed below. It's possible that only very large power plants can generate the power needed to produce antigravity, and the antigravity plate may be an early attempt to miniaturize the system found on starships. This would mean the human and Covenant technology were not that far apart in this regard, with humans lacking the technology needed to miniaturize gravity/antigravity generators.

===Forerunner===
Most [[Forerunner]] ships or installations possessed artificial gravity without the use of centrifugal force. This was achieved through the use of energy fields known as [[buffer field]]s.<ref name="c304">'''Halo: Cryptum''', ''page 304''</ref> The science behind these fields, or whether Covenant and human artificial gravity devices operate by a similar principle, is unknown.

==Trivia==
In all of the ''Halo'' games, all human vessels or stations seem to employ sophisticated, unseen artificial gravity generators to simulate gravity, as opposed to rotating sections. Originally, it was widely assumed that the UNSC gained their current artificial gravity technology from the Covenant, and had to use rotating centrifuges to mimic gravity prior to this. According to ''[[Halo: The Fall of Reach]]'', human ships were still undergoing tests with reverse-engineered artificial gravity by 2552, while newer sources such as ''[[Halo: Contact Harvest]]'' portray artificial gravity present even on automated freighters.

==Notes==
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==Sources==
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==Related links==
===Internal===
*[[Anti-gravity technology]]

===External===
*[[Wikipedia:gravitation|Gravity on Wikipedia]]
*[[Wikipedia:Artificial gravity|Artificial gravity on Wikipedia]]
[[Category:Gravity technology]]