Editing Solar sail (section)

===Planetary Society LightSail Projects===
{{main|LightSail}}

On June 21, 2005, a joint private project between [[Planetary Society]], [[Cosmos Studios]] and [[Russian Academy of Science]]  launched a prototype sail ''Cosmos 1''  from a submarine in the [[Barents Sea]], but the [[Volna]] rocket failed, and the spacecraft failed to reach orbit. They intended to use the sail to gradually raise the spacecraft to a higher Earth orbit over a mission duration of one month. The launch attempt sparked public interest according to Louis Friedman.<ref>{{cite web|last=Friedman|first=Louis|title=The Rise and Fall of Cosmos 1|url=http://sail.planetary.org/story-part-2.html|work=sail.planetary.org}}</ref> Despite the failed launch attempt of Cosmos 1, [[The Planetary Society]] received applause for their efforts from the space community and sparked a rekindled interest in solar sail technology.

On Carl Sagan's 75th birthday (November 9, 2009) the Planetary Society announced plans<ref>{{cite news| url=https://www.nytimes.com/2009/11/10/science/space/10solar.html| title=Setting Sail Into Space, Propelled by Sunshine| last=Overbye| first=Dennis| work=The New York Times| date=November 9, 2009| quote=Planetary Society, ... the next three years, ... series of solar-sail spacecraft dubbed LightSails|access-date=18 May 2012}}</ref> to make three further attempts, dubbed [[LightSail#LightSail-1|LightSail-1]], [[LightSail#LightSail-2|-2]], and -3.<ref name="planetary">{{cite web|url=http://www.planetary.org/explore/projects/lightsail-solar-sailing/lightsail-mission-faq.html |archive-url=https://web.archive.org/web/20120430105820/http://www.planetary.org/explore/projects/lightsail-solar-sailing/lightsail-mission-faq.html |url-status=dead |archive-date=30 April 2012 |title=LightSail Mission FAQ |publisher=[[The Planetary Society]] |access-date=18 May 2012 }}</ref> The new design will use a 32 m<sup>2</sup> Mylar sail, deployed in four triangular segments like NanoSail-D.<ref name="planetary"/> The launch configuration is a 3U [[CubeSat]] format, and as of 2015, it was scheduled as a secondary payload for a 2016 launch on the first [[SpaceX]] [[Falcon Heavy]] launch.<ref>{{cite AV media |last1=Nye| first1=Bill |title=Kickstart LightSail |url=https://www.youtube.com/watch?v=kDBzRa9RzfM | archive-url=https://ghostarchive.org/varchive/youtube/20211117/kDBzRa9RzfM| archive-date=2021-11-17 | url-status=live|time=3:20 |access-date=15 May 2015 }}{{cbignore}}</ref>

"[[LightSail#LightSail-1|LightSail-1]]" was launched on 20 May 2015.<ref name="NBCNEWS">{{Cite web|url=https://www.nbcnews.com/science/space/blastoff-x-37b-space-plane-lightsail-solar-sail-go-space-n361931|title=Blastoff! X-37B Space Plane and LightSail Solar Sail Go Into Orbit|website=NBC News|date=20 May 2015 }}</ref> The purpose of the test was to allow a full checkout of the satellite's systems in advance of LightSail-2.  Its deployment orbit was not high enough to escape Earth's atmospheric drag and demonstrate true solar sailing.

[[File:LightSail 2 with deployed solar sail.png|thumb|Deployed LightSail-2]]

"[[LightSail#LightSail-2|LightSail-2]]" was launched on 25 June 2019, and deployed into a much higher low Earth orbit. Its solar sails were deployed on 23 July 2019.<ref name="NYT-20190723">{{cite news |last=Stirone |first=Shannon |title=LightSail 2 Unfurls, Next Step Toward Space Travel by Solar Sail - The Planetary Society deployed LightSail 2, aiming to further demonstrate the potential of the technology for space propulsion. |url=https://www.nytimes.com/2019/07/23/science/lightsail-solar-sail.html |date=July 23, 2019 |work=[[The New York Times]] |access-date=July 24, 2019 }}</ref> It reentered the atmosphere on 17 November 2022. LightSail-2 successfully demonstrated propulsion by solar sail.<ref>https://www.planetary.org/sci-tech/lightsail</ref>