Editing Space elevator (section)

==History==
===Early concept===
The idea of the space elevator appears to have developed independently in different times and places. The earliest models originated with two Russian scientists in the late nineteenth century. In his 1895 collection ''Dreams of Earth and Sky'',<ref>{{Cite book |last=Tsiolkovsky |first=Konstanti |title=Dreams of Earth and Sky |publisher=Athena Books |year=2004 |isbn=9781414701639}}</ref> [[Konstantin Tsiolkovsky]] envisioned a massive sky ladder to reach the stars as a way to overcome gravity.<ref name=":0">{{Cite web |last=Derek J. Pearson |date=2022 |title=The Steep Climb to Low Earth Orbit: A History of the Space Elevator Community's Battle Against the Rocket Paradigm. |url=https://vtechworks.lib.vt.edu/server/api/core/bitstreams/4e65652b-115e-4410-8aec-e17dbf33a8a9/content}}</ref><ref name="NASASci">{{cite web |title=The Audacious Space Elevator |url=https://science.nasa.gov/headlines/y2000/ast07sep_1.htm |url-status=dead |archive-url=https://web.archive.org/web/20080919070924/https://science.nasa.gov/headlines/y2000/ast07sep_1.htm |archive-date=19 September 2008 |access-date=27 September 2008 |publisher=NASA Science News}}</ref><ref name="JBIS1999">{{cite journal |last1=Landis |first1=Geoffrey A. |last2=Cafarelli |first2=Craig |name-list-style=amp |year=1999 |others=Presented as paper IAF-95-V.4.07, 46th International Astronautics Federation Congress, Oslo, Norway, 2-6 October 1995 |title=The Tsiolkovski Tower Reexamined |journal=Journal of the British Interplanetary Society |volume=52 |pages=175–180 |bibcode=1999JBIS...52..175L}}</ref>  Decades later, in 1960, [[Yuri Artsutanov]] independently developed the concept of a "Cosmic Railway", a space elevator tethered from an orbiting satellite to an anchor on the equator, aiming to provide a safer and more efficient alternative to rockets.<ref>Artsutanov, Y. V Kosmos na Elektrovoze (Into Space by Funicular Railway). Komsomolskaya Pravda (Young Communist Pravda), 31 July 1960. Contents described in Lvov, ''Science'' 158:946, 17 November 1967</ref><ref>{{Cite journal |last=Lvov |first=Vladimir |date=1967-11-17 |title=Sky-Hook: Old Idea |url=https://www.science.org/doi/10.1126/science.158.3803.946 |journal=Science |language=en |volume=158 |issue=3803 |pages=946–947 |doi=10.1126/science.158.3803.946 |pmid=17753605 |bibcode=1967Sci...158..946L |issn=0036-8075|url-access=subscription }}</ref><ref>{{cite web |last=Artsutanov |first=Yu |year=1960 |title=To the Cosmos by Electric Train |url=http://liftport.com/files/Artsutanov_Pravda_SE.pdf |archive-url=https://web.archive.org/web/20060506100948/http://liftport.com/files/Artsutanov_Pravda_SE.pdf |archive-date=6 May 2006 |access-date=5 March 2006 |work=liftport.com |publisher=Young Person's Pravda}}</ref> In 1966, [[John O. Isaacs|Isaacs]] and his colleagues introduced the concept of the 'Sky-Hook', proposing a satellite in geostationary orbit with a cable extending to Earth.<ref name=":1">{{cite journal |author=Isaacs |first1=J. D. |last2=Vine |first2=A. C. |last3=Bradner |first3=H. |last4=Bachus |first4=G. E. |year=1966 |title=Satellite Elongation into a True 'Sky-Hook' |journal=Science |volume=151 |issue=3711 |pages=682–683 |bibcode=1966Sci...151..682I |doi=10.1126/science.151.3711.682 |pmid=17813792 |s2cid=32226322}}</ref>

=== Innovations and designs ===
The space elevator concept reached America in 1975 when [[Jerome Pearson]] began researching the idea, inspired by [[Arthur C. Clarke]]'s 1969 speech before Congress. After working as an engineer for NASA and the Air Force Research Laboratory, he developed a design for an "Orbital Tower", intended to harness Earth's rotational energy to transport supplies into low Earth orbit. In his publication in ''[[Acta Astronautica]]<ref name=":2">{{cite journal |author=Pearson, J. |year=1975 |title=The orbital tower: a spacecraft launcher using the Earth's rotational energy |url=http://www.star-tech-inc.com/papers/tower/tower.pdf |journal=Acta Astronautica |volume=2 |issue=9–10 |pages=785–799 |bibcode=1975AcAau...2..785P |citeseerx=10.1.1.530.3120 |doi=10.1016/0094-5765(75)90021-1}}</ref>'', the cable would be thickest at geostationary orbital altitude where tension is greatest, and narrowest at the tips to minimize weight. He proposed extending a counterweight to 144,000 kilometers (89,000 miles) as without a large counterweight, the upper cable would need to be longer due to the way [[Gravity|gravitational]] and centrifugal forces change with distance from Earth. His analysis included the Moon's gravity, wind, and moving payloads. Building the elevator would have required thousands of [[Space Shuttle]] trips, though material could be transported once a minimum strength strand reached the ground or be manufactured in space from [[Asteroid mining|asteroidal]] or [[In-situ resource utilization|lunar ore]]. Pearson's findings, published in ''Acta Astronautica'', caught Clarke's attention and led to technical consultations for Clarke's science fiction novel ''[[The Fountains of Paradise]]'' (1979),<ref>{{Cite book |last=Clarke |first=Arthur C. |title=The fountains of Paradise. Harcourt Brace Jovanovich |year=1979 |publisher=Harcourt Brace Jovanovich |isbn=9780151327737}}</ref> which features a space elevator.<ref>{{Cite web |last=Boucher |first=Marc |date=2013-04-08 |title=The Space Elevator: 'Thought Experiment', or Key to the Universe? |url=https://spaceref.com/newspace-and-tech/the-space-elevator-thought-experiment-or-key-to-the-universe-by-sir-arthur-c-clarke/ |access-date=2024-05-30 |website=SpaceRef |language=en-US}}</ref><ref>{{Cite journal |last=Edwards |first=Bradley C. |date=2004 |title=A Space Elevator Based Exploration Strategy |url=http://dx.doi.org/10.1063/1.1649650 |journal=AIP Conference Proceedings |volume=699 |pages=854–862 |publisher=AIP |doi=10.1063/1.1649650|bibcode=2004AIPC..699..854E |url-access=subscription }}</ref>

The first gathering of multiple experts who wanted to investigate this alternative to space flight took place at the 1999 NASA conference 'Advanced Space Infrastructure Workshop on Geostationary Orbiting Tether Space Elevator Concepts'. in Huntsville, Alabama.<ref name=":0"/> D.V. Smitherman, Jr., published the findings in August of 2000 under the title ''Space Elevators: An Advanced Earth-Space Infrastructure for the New Millennium'', concluding that the space elevator could not be built for at least another 50 years due to concerns about the cable's material, deployment, and upkeep.<ref name="Smitherman">{{cite report |editor-last=Smitherman, Jr. |editor-first=D.V. |date=August 2000 |title=Space Elevators: An Advanced Earth-Space Infrastructure for the New Millennium |url=https://nss.org/wp-content/uploads/2000-Space-Elevator-NASA-CP210429.pdf |publisher=[[NASA]] |url-status=live |archive-url=https://web.archive.org/web/20150328040627/http://www.nss.org/resources/library/spaceelevator/2000-SpaceElevator-NASA-CP210429.pdf |archive-date=2015-03-28}}</ref>{{Page needed|date=August 2024|reason=Lengthy document; please provide applicable page.}}

[[Bradley C. Edwards|Dr. B.C. Edwards]] suggested that a {{convert|100,000|km|mi|abbr=on}} long paper-thin ribbon, utilizing  a carbon nanotube composite material could solve the tether issue due to its high tensile strength and low weight <ref name="EDWARDS_PHASE_I_2000_472Edwards.html">[[Bradley C. Edwards]], "[http://www.niac.usra.edu/studies/472Edwards.html The Space Elevator]".</ref> The proposed wide-thin ribbon-like cross-section shape instead of earlier circular cross-section concepts would increase survivability against meteoroid impacts. With support from [[NASA Institute for Advanced Concepts]] (NIAC), his work involved more than 20 institutions and 50 participants.<ref name=":3">{{cite report |last=Edwards |first=Bradley C. |author-link=Bradley C. Edwards |date=2003-03-01 |title=The Space Elevator: NIAC Phase II Final Report |url=http://images.spaceref.com/docs/spaceelevator/521Edwards.pdf |publisher=Eureka Scientific}}</ref>{{rp|2}} The Space Elevator NIAC Phase II Final Report, in combination with the book ''The Space Elevator'': ''A Revolutionary Earth-to-Space Transportation System'' (Edwards and Westling, 2003)<ref>{{Cite book |last=Bradley C. Edwards; Eric A. Westling |title=The Space Elevator: A Revolutionary Earth-to-Space Transportation System |publisher=BC Edwards |year=2003 |isbn=9780974651712}}</ref> summarized all effort to design a space elevator<ref name=":3" />{{Page needed|date=August 2024|reason=Lengthy document; please provide applicable page.}} including deployment scenario, climber design, power delivery system, [[Space debris|orbital debris]] avoidance, anchor system, surviving [[atomic oxygen]], avoiding lightning and hurricanes by locating the anchor in the western equatorial Pacific, construction costs, construction schedule, and environmental hazards.<ref name="Edwards" /><ref name="Smitherman"/>{{Page needed|date=August 2024|reason=Lengthy document; please provide applicable page.}}<ref>Science @ NASA, [https://science.nasa.gov/headlines/y2000/ast07sep_1.htm "Audacious & Outrageous: Space Elevators"] {{webarchive|url=https://web.archive.org/web/20080919070924/https://science.nasa.gov/headlines/y2000/ast07sep_1.htm|date=19 September 2008}}, September 2000.</ref> Additionally, he researched the structural integrity and load-bearing capabilities of space elevator cables, emphasizing their need for high tensile strength and resilience. His space elevator concept never reached NIAC's third phase, which he attributed to submitting his final proposal during the week of the [[Space Shuttle Columbia]] disaster.<ref name=":0" />

=== 21st century advancements ===
To speed space elevator development, proponents have organized several [[Space Elevator Competitions|competitions]], similar to the [[Ansari X Prize]], for relevant technologies.<ref>{{cite web |url=http://www.nbcnews.com/id/5792719 |archive-url=https://web.archive.org/web/20131214181227/http://www.nbcnews.com/id/5792719/ |url-status=dead |archive-date=14 December 2013 |title=Space elevator contest proposed |first=Alan |last=Boyle |publisher=NBC News |date=27 August 2004}}</ref><ref>{{cite web |title=The Space Elevator – Elevator:2010 |url=http://www.elevator2010.org/ |url-status=dead |archive-url=https://web.archive.org/web/20070106211508/http://www.elevator2010.org/ |archive-date=6 January 2007 |access-date=5 March 2006}}</ref> Among them are [[Elevator:2010]], which organized annual competitions for climbers, ribbons and power-beaming systems from 2005 to 2009, the Robogames Space Elevator Ribbon Climbing competition,<ref>{{cite web |url=http://robogames.net/rules/climbing.php |title=Space Elevator Ribbon Climbing Robot Competition Rules |access-date=5 March 2006 |archive-url = https://web.archive.org/web/20050206100051/http://robolympics.net/rules/climbing.shtml|archive-date=6 February 2005}}</ref> as well as NASA's [[Centennial Challenges]] program, which, in March 2005, announced a partnership with the Spaceward Foundation (the operator of Elevator:2010), raising the total value of prizes to US$400,000.<ref>{{cite web |url=http://www.nasa.gov/home/hqnews/2005/mar/HQ_m05083_Centennial_prizes.html |title=NASA Announces First Centennial Challenges' Prizes |year=2005 |access-date=5 March 2006 |archive-date=8 June 2005 |archive-url=https://web.archive.org/web/20050608083813/http://www.nasa.gov/home/hqnews/2005/mar/HQ_m05083_Centennial_prizes.html |url-status=dead }}</ref><ref>{{cite web |url=http://www.space.com/news/050323_centennial_challenge.html |title=NASA Details Cash Prizes for Space Privatization |first=Robert Roy |last=Britt |work=Space.com |date=24 March 2005 |access-date=5 March 2006}}</ref>
The first European Space Elevator Challenge (EuSEC) to establish a climber structure took place in August 2011.<ref>{{cite web |title=What's the European Space Elevator Challenge? |url=http://eusec.warr.de/?eusec |publisher=European Space Elevator Challenge |access-date=21 April 2011 |archive-date=15 August 2011 |archive-url=https://web.archive.org/web/20110815214545/http://eusec.warr.de/?eusec |url-status=dead }}</ref>

In 2005, "the [[LiftPort Group]] of space elevator companies announced that it will be building a carbon nanotube manufacturing plant in [[Millville, New Jersey]], to supply various glass, plastic and metal companies with these strong materials. Although LiftPort hopes to eventually use carbon nanotubes in the construction of a {{convert|100,000|km|mi|abbr=on}} space elevator, this move will allow it to make money in the short term and conduct research and development into new production methods."<ref name="universetoday">{{cite news |url=http://www.universetoday.com/am/publish/liftport_manufacture_nanotubes.html?2742005 |title=Space Elevator Group to Manufacture Nanotubes |date=27 April 2005 |first=Fraser |last=Cain |work=Universe Today |access-date=5 March 2006}}</ref> Their announced goal was a space elevator launch in 2010. On 13 February 2006, the LiftPort Group announced that, earlier the same month, they had tested a mile of "space-elevator tether" made of carbon-fiber composite strings and fiberglass tape measuring {{cvt|5|cm|in}} wide and {{cvt|1|mm|in}} (approx. 13 sheets of paper) thick, lifted with balloons.<ref>{{cite news |url=http://www.newscientistspace.com/article/dn8725.html |title=Space-elevator tether climbs a mile high |date=15 February 2006 |work=New Scientist |first=Kimm |last=Groshong |access-date=5 March 2006}}</ref> In April 2019, Liftport CEO Michael Laine admitted little progress has been made on the company's lofty space elevator ambitions, even after receiving more than $200,000 in seed funding. The carbon nanotube manufacturing facility that Liftport announced in 2005 was never built.<ref>{{cite web |date=28 March 2019 |title=If a space elevator was ever going to happen, it could have gotten its start in N. J. Here's how it went wrong |url=https://www.nj.com/cumberland/2019/04/if-a-space-elevator-was-ever-going-to-happen-it-could-have-gotten-its-start-in-nj-heres-how-it-went-wrong.html |access-date=11 May 2019 |publisher=NJ.com}}</ref>

In 2007, [[Elevator:2010]] held the 2007 Space Elevator games, which featured US$500,000 awards for each of the two competitions ($1,000,000 total), as well as an additional $4,000,000 to be awarded over the next five years for space elevator related technologies.<ref>[https://web.archive.org/web/20100118153108/http://www.spaceward.org/elevator2010 Elevator:2010 – The Space Elevator Challenge]. spaceward.org.</ref> No teams won the competition, but a team from [[MIT]] entered the first 2-gram (0.07&nbsp;oz), 100-percent carbon nanotube entry into the competition.<ref>[https://web.archive.org/web/20071101081423/http://www.spaceward.org/games07Wrapup.html Spaceward Games 2007]. The Spaceward Foundation.</ref> Japan held an international conference in November 2008 to draw up a timetable for building the elevator.<ref name="JapanUKTimes">{{cite news |last=Lewis |first=Leo |date=22 September 2008 |title=Japan hopes to turn sci-fi into reality with elevator to the stars |url=http://www.thetimes.co.uk/tto/news/world/article1967078.ece |archive-url=https://archive.today/20200226134504/http://www.thetimes.co.uk/tto/news/world/article1967078.ece |url-status=dead |archive-date=26 February 2020 |access-date=23 May 2010 |work=[[The Times]] |location=London, England}} Lewis, Leo; News International Group; accessed 22 September 2008.</ref>

In 2012, the [[Obayashi Corporation]] announced that it could build a space elevator by 2050 using carbon nanotube technology.<ref name="physorg_obayashi">{{cite news| url=http://www.physorg.com/news/2012-02-japan-builder-eyes-space-elevator.html | website=Phys.org | title=Going up: Japan builder eyes space elevator | date=22 February 2012}}</ref> The design's passenger climber would be able to reach the level of geosynchronous equatorial orbit (GEO) after an 8-day trip.<ref>{{cite news| url=https://www.smithsonianmag.com/smart-news/researchers-take-tiny-first-step-toward-space-elevator-180970212/ | title=Japan Takes Tiny First Step Toward Space Elevator | date=5 September 2018 |work=Smithsonian Magazine |first=Jason |last=Daley}}</ref> Further details were published in 2016.<ref>{{cite journal |last1=Ishikawa |first1=Y. |date=2016 |title=Obayashi Corporation's Space Elevator Construction Concept |url=https://ui.adsabs.harvard.edu/abs/2016JBIS...69..227I/abstract |journal=Journal of the British Interplanetary Society |volume=69 |issue= |pages=227–239 |doi= |bibcode=2016JBIS...69..227I |access-date=5 January 2021}}</ref>

In 2013, the [[International Academy of Astronautics]] published a technological feasibility assessment which concluded that the critical capability improvement needed was the tether material, which was projected to achieve the necessary [[specific strength]] within 20 years. The four-year long study looked into many facets of space elevator development including missions, development schedules, financial investments, revenue flow, and benefits. It was reported that it would be possible to operationally survive smaller impacts and avoid larger impacts, with meteors and space debris, and that the estimated cost of lifting a kilogram of payload to GEO and beyond would be $500.<ref name="ISEC_SE_way_forward_2013"/>{{rp|10–11, 207–208}}<ref>{{cite report |editor-last1=Swan |editor-first1=Peter |editor-last2=Penny |editor-first2=Rober "Skip" |editor-last3=Swan |editor-first3=Cathy |date=2010 |title=Space Elevator Survivability, Space Debris Mitigation |url=https://static1.squarespace.com/static/5e35af40fb280744e1b16f7b/t/5e5c1d06483fcf20335da699/1583095099789/2010StudyReport_SpaceElevatorSpaceDebris.pdf |publisher=International Space Elevator Consortium}}{{Self-published source|reason=Published via Lulu.com.|date=August 2024}}</ref>{{Page needed|date=August 2024|reason=Lengthy document; please provide applicable page.}}

In 2014, Google X's Rapid Evaluation R&D team began the design of a Space Elevator, eventually finding that no one had yet manufactured a perfectly formed [[carbon nanotube]] strand longer than a meter. They thus put the project in "deep freeze" and also keep tabs on any advances in the carbon nanotube field.<ref>{{cite web|last=Gayomali|first=Chris|title=Google X Confirms The Rumors: It Really Did Try To Design A Space Elevator|url=http://www.fastcompany.com/3029138/world-changing-ideas/google-x-confirms-the-rumors-it-really-did-try-to-design-a-space-elevat?partner=rss|work=Fast Company |date=15 April 2014 |access-date=17 April 2014}}</ref>

In 2018, researchers at Japan's [[Shizuoka University]] launched STARS-Me, two [[CubeSat]]s connected by a tether, which a mini-elevator will travel on.<ref>{{Cite web | url=https://www.nbcnews.com/mach/science/colossal-elevator-space-could-be-going-sooner-you-ever-imagined-ncna915421 | title=A colossal elevator to space could be going up sooner than you ever imagined |work=NBC News |date=2 October 2018 |first=Scott |last=Snowden}}</ref><ref>{{cite web |url=https://www.curbed.com/2018/9/12/17851500/space-elevator-japan-news |title=Japan is trying to build an elevator to space |publisher=Curbed.com |first=Meghan |last=Barber |date=12 September 2018 |access-date=18 September 2018}}</ref> The experiment was launched as a test bed for a larger structure.<ref>{{Cite web | url=https://gizmodo.com/japan-testing-miniature-space-elevator-near-the-interna-1828800558 |title = Japan Testing Miniature Space Elevator Near the International Space Station| date=4 September 2018 }}</ref>

In 2019, the [[International Academy of Astronautics]] published "Road to the Space Elevator Era",<ref>{{cite book |vauthors=Swan PA, Raitt DI, Knapman JM, Tsuchida A, Fitzgerald MA, Ishikawa Y |title=Road to the Space Elevator Era |date=30 May 2019 |publisher=International Academy of Astronautics |isbn=978-0-9913370-3-3 |url=https://www.heinleinbooks.com/product-page/road-to-the-space-elevator-era}}</ref> a study report summarizing the assessment of the space elevator as of summer 2018. The essence is that a broad group of space professionals gathered and assessed the status of the space elevator development, each contributing their expertise and coming to similar conclusions: (a) Earth Space Elevators seem feasible, reinforcing the IAA 2013 study conclusion (b) Space Elevator development initiation is nearer than most think. This last conclusion is based on a potential process for manufacturing macro-scale single crystal [[graphene]]<ref name="azom.com">{{Cite web |date=23 July 2018 |title=Space Elevator Technology and Graphene: An Interview with Adrian Nixon |url=https://www.azom.com/article.aspx?ArticleID=16371}}</ref> with higher [[specific strength]] than [[carbon nanotube]]s.