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{{short description|Hypothetical satellite which would use a solar sail to modify its orbit}}

A '''statite''' (a [[portmanteau]] of the words ''static'' and ''satellite'') is a hypothetical type of [[artificial satellite]] that employs a [[solar sail]] to continuously modify its [[orbit]] in ways that [[gravity]] alone would not allow. Typically, a statite would use the solar sail to "hover" in a location that would not otherwise be available as a stable [[geosynchronous orbit]]. Statites have been proposed that would remain in fixed locations high over [[Earth]]'s poles, using reflected [[sunlight]] to counteract the gravity pulling them down. Statites might also employ their sails to change the shape or velocity of more conventional orbits, depending upon the purpose of the particular statite.

The concept of the statite was invented independently and at about the same time by [[Robert L. Forward]]<ref name="Forward Patent">{{Ref patent | country = US | number = 5183225 | status = patent | title = Statite: Spacecraft That Utilizes Light Pressure and Method of Use |  gdate = 1993-02-02 | pridate =  | inventor = Robert L. Forward | invent1 = Robert | invent2 = Forward | assign1 =  | assign2 =  | class = }}</ref> (who coined the term "statite") and [[Colin R. McInnes|Colin McInnes]], who used the term "halo orbit"<ref>McInnes, C. R. and Simmons, J. F. L.: "Halo Orbits for Solar Sails—Dynamics and Applications", ''ESA Journal'', Vol. 13, 1989, pp. 229-234</ref> (not to be confused with the type of [[halo orbit]] discovered by Robert Farquhar). Subsequently, the terms "non-[[Keplerian orbit]]" and "artificial [[Lagrange point]]" have been used as a generalization of the above terms.

No statites have been deployed to date, as solar sail technology remains in its infancy. NASA's cancelled ''[[Sunjammer (spacecraft)|Sunjammer]]'' solar sail mission had the stated objective of flying to an artificial Lagrange point near the Earth/Sun L1 point, to demonstrate the feasibility of the Geostorm<ref>[http://wiki.solarsails.info/index.php?title=Geostorm Geostorm]</ref> [[geomagnetic storm]] warning mission concept proposed by NOAA's [[Patricia Mulligan]].<ref>{{cite journal|last1=Mulligan|first1=Patricia|title=Solar Sails for the Operational Space Community|journal=Spaceviews|date=August 1998|volume=8|issue=3–4}}</ref> A constellation of statites have been proposed for performing a rendezvous with an [[interstellar object]].<ref>{{cite news
 | title=To catch an interstellar visitor, use a solar-powered space slingshot
 | first=Sara | last=Cody | date=May 6, 2020
 | publisher=MIT News, Department of Aeronautics and Astronautics
 | url=https://news.mit.edu/2020/catch-interstellar-visitor-use-solar-powered-space-statite-slingshot-0506
 | access-date=2025-01-06 }}</ref>

==See also==
* [[Dyson bubble]]
* [[List of hypothetical technologies]]
* [[Solar mirror]]
* [[Space sunshade]]

==References==
{{Reflist}}

[[Category:Astrodynamics]]
[[Category:Hypothetical technology]]
[[Category:Spaceflight concepts]]

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