View source for Cosmos 1

{{Short description|Solar sail project}}
{{About|the solar sail project and spacecraft|the Soviet satellite|Kosmos 1|the rocket|Kosmos-1}}
{{Use American English|date=November 2021}}
{{Use dmy dates|date=November 2021}}
{{Infobox spaceflight
| name              = Cosmos 1
| image             = Cosmos1 in orbit.jpg
| image_caption     = An artist's rendering of ''Cosmos 1'' orbiting the [[Earth]]
| image_size        = 300px

| mission_type      = [[Technology demonstration]]<ref name="Planetary">{{cite web|url=http://www.planetary.org/explore/topics/space_missions/private_missions/cosmos1.html|title=Private Mission - Cosmos 1
|publisher=The Planetary Society| archive-url=https://web.archive.org/web/20070929115043/http://www.planetary.org/explore/topics/space_missions/private_missions/cosmos1.html |archive-date=29 September 2007|access-date=21 November 2021}}</ref>
| operator          = [[The Planetary Society]]
| website           = 
| mission_duration  = Failed to orbit<br/>30 days (planned)

| spacecraft_bus    = 
| manufacturer      = The Planetary Society
| launch_mass       = {{cvt|100|kg}}
| dimensions        = {{cvt|30|m}} in diameter
| power             =

| launch_date       = 21 June 2005, 19:46:09 [[Coordinated Universal Time|UTC]]
| launch_rocket     = [[Volna]]
| launch_site       = [[Russian submarine K-496 Borisoglebsk|K-496 ''Borisoglebsk'']], [[Barents Sea]]
| launch_contractor = [[Makeyev Rocket Design Bureau]]

| entered_service   = 
| destroyed         = Failed to orbit
| last_contact      = 
| decay_date        =

| orbit_reference   = [[Geocentric orbit]] (planned)
| orbit_regime      = [[Low Earth orbit]]
| orbit_altitude    = {{cvt|800|km}}
| orbit_inclination = 80.00°
| orbit_period      = 
| apsis             = gee
}}

'''Cosmos 1''' was a project by [[Cosmos Studios]] and [[The Planetary Society]] to test a [[solar sail]] in space. As part of the project, an uncrewed solar-sail spacecraft named ''Cosmos 1'' was launched into space at 19:46:09 [[Coordinated Universal Time|UTC]] (15:46:09 [[Eastern Daylight Time|EDT]]) on 21 June 2005 from the submarine {{ship|Russian submarine|Borisoglebsk|K-496|2}} in the [[Barents Sea]]. However, a rocket failure prevented the spacecraft from reaching its intended orbit.<ref>{{cite news|title=Russians say solar-sail vehicle was lost|date=June 21, 2005|url=https://www.nbcnews.com/id/wbna8304717|publisher=Associated Press|website=NBC News|access-date=May 7, 2023}}</ref> Once in orbit, the spacecraft was supposed to deploy a large sail, upon which [[photon]]s from the [[Sun]] would [[Radiation pressure|push]], thereby increasing the spacecraft's velocity (the contributions from the [[solar wind]] are similar, but of much smaller magnitude).

Had the mission been successful, it would have been the first ever orbital use of a solar sail to speed up a spacecraft, as well as the first space mission by a [[space advocacy|space advocacy group]]. The project budget was US$4 million. The Planetary Society planned to raise another US$4 million for ''Cosmos 2'', a reimplementation of the experiment provisionally to be launched on a [[Soyuz (rocket family)|Soyuz]] resupply mission to the [[International Space Station]] (ISS). The Discovery Channel was an early investor.<ref>[http://www.planetary.org/programs/projects/solar_sailing/20080623.html Cosmos 2] {{webarchive|url=https://web.archive.org/web/20100421003559/http://www.planetary.org/programs/projects/solar_sailing/20080623.html|date=2010-04-21}}.</ref> However, advances in technology and the greater availability of lower-mass piggyback slots on more launch vehicles led to a redesign similar to [[NanoSail-D]], called [[LightSail-1]], announced in November 2009.<ref name="LightSailRelease">{{cite web |url=http://www.planetary.org/about/press/releases/2009/1109_Planetary_Society_to_Sail_Again_with.html|title=LightSail Release|date=9 November 2009|publisher=The Planetary Society|access-date=26 April 2010}}</ref>

== Planned mission profile ==
To test the solar sail concept, the Cosmos 1 project launched an [[Orbital spaceflight|orbital spacecraft]] they named ''Cosmos 1'' with a full complement of eight sail blades on 21 June 2005; the summer [[solstice]]. The spacecraft had a mass of {{cvt|100|kg}} and consisted of eight triangular sail blades, which would be deployed from a central hub after launch by the inflating of structural tubes. The sail blades were each {{cvt|15|m}} long, had a total surface area of {{cvt|600|m2}}, and were made of [[metallized polyethylene terephthalate|aluminized-reinforced PET film (MPET)]].

The spacecraft was launched on a [[Volna]] [[launch vehicle]] (a converted [[SS-N-18]] [[intercontinental ballistic missile]] (ICBM)) from the [[Russia]]n [[Delta-class submarine|Delta III submarine]] {{ship|Russian submarine|Borisoglebsk|K-496|2}}, submerged in the [[Barents Sea]]. The spacecraft's initial circular orbit would have been at an altitude of about {{cvt|800|km}}, where it would have unfurled the sails. The sails would then have gradually raised the spacecraft to a higher Earth orbit. "''Cosmos 1'' might boost its orbit {{cvt|50|to|100|km}} over the expected 30-day life of the mission", said Louis Friedman of The Planetary Society.<ref name=Deprecated-Original-Article>{{cite news|title=Solar Sail|first=Thomas H. II|last=Maugh|first2=Monte|last2=Morin|date=20 June 2005 |url=http://www.latimes.com/news/science/la-sci-solarsail20jun20,1,2584884.story?coll=la-news-science&ctrack=1&cset=true|newspaper=Los Angeles Times|access-date=20 June 2005}}</ref><ref name=Archived-Article-Abstract>{{cite news|title=Solar Sail Is in Space, but Where?; The Planetary Society loses contact with the satellite but detects a faint signal hours later.|first=Thomas H. II|last=Maugh|author2=Morin, Monte|date=2005-06-22|url=https://pqasb.pqarchiver.com/latimes/access/856856791.html?dids=856856791:856856791&FMT=ABS&FMTS=ABS:FT&type=current&date=Jun+22%2C+2005&author=Thomas+H.+Maugh+II+and+Monte+Morin&pub=Los+Angeles+Times&edition=&startpage=A.1&desc=Solar+Sail+Is+in+Space%2C+but+Where%3F%3B+The+Planetary+Society+loses+contact+with+the+satellite+but+detects+a+faint+signal+hours+later|archive-url=https://web.archive.org/web/20110525093221/http://pqasb.pqarchiver.com/latimes/access/856856791.html?dids=856856791:856856791&FMT=ABS&FMTS=ABS:FT&type=current&date=Jun+22,+2005&author=Thomas+H.+Maugh+II+and+Monte+Morin&pub=Los+Angeles+Times&edition=&startpage=A.1&desc=Solar+Sail+Is+in+Space,+but+Where%3F%3B+The+Planetary+Society+loses+contact+with+the+satellite+but+detects+a+faint+signal+hours+later|url-status=dead|archive-date=25 May 2011|access-date=2007-09-04}}</ref>

The mission was expected to end within a month of launch, as the [[BoPET|mylar]] of the blades would degrade in sunlight.

=== Possible beam propulsion ===
The solar-sail craft could also have been used to measure the effect of artificial [[microwave]]s aimed at it from a [[radar]] installation. A {{cvt|70|m}} dish at the [[Goldstone Deep Space Communications Complex|Goldstone]] facility of [[NASA Deep Space Network]] would have been used to irradiate the sail with a 450 [[Watt|kW]] beam. This experiment in [[beam-powered propulsion]] would only have been attempted after the prime mission objective of controlled solar-sail flight was achieved.

=== Tracking ===
The craft would have been visible to the [[naked eye]] from most of the Earth's surface: the planned orbit had an [[Orbital inclination|inclination]] of 80°, so it would have been visible from [[latitude]]s of up to approximately 80° north and south.

A network of tracking stations around the world, including the [[Tarusa]] station, {{cvt|121|km}} south of [[Moscow]], and the [[Space Sciences Laboratory]] at the [[University of California, Berkeley]], tried to maintain contact with the solar sail during the mission. Mission control was based primarily at the Russian company [[NPO Lavochkin]] in Moscow; a center that the Planetary Society calls Mission Operations Moscow (MOM).

== Physics ==
{{main|Solar sail}}

The craft would have been gradually accelerating during each orbit as a result of the [[radiation pressure]] of photons colliding with the sails. As photons reflected from the surface of the sails, they would transfer [[momentum]] to them. As there would be no air resistance to oppose the velocity of the spacecraft, [[acceleration]] would be proportional to the number of photons colliding with it per unit time. Sunlight amounts to a tiny {{val|5|e=-4|u=m/s2}} acceleration in the vicinity of the Earth. Over one day, the spacecraft's speed would reach {{cvt|45|m/s}}; in 100 days its speed would be {{cvt|4500|m/s}}, in 2.74 years {{cvt|45000|m/s}}.

At that speed, a craft would reach [[Pluto]], a very distant dwarf planet in the [[Solar System]], in less than 5 years,<ref name=ambitious-experiment-BBC-report>{{cite journal|title=''Cosmos 1'': Sailing on sunlight|journal=BBC News Science/Nature|date=22 June 2005|url=http://news.bbc.co.uk/1/hi/sci/tech/4104282.stm|access-date=2007-09-04}}</ref> although in practice the acceleration of a sail drops dramatically as the spacecraft gets farther from the [[Sun]]. However, in the vicinity of Earth, a solar sail's acceleration is larger than that of some other propulsion techniques; for example, the [[ion thruster]]-propelled [[SMART-1]] spacecraft has a maximum acceleration of {{val|2|e=-4|u=m/s2}}, which allowed SMART-1 to achieve lunar orbit in November 2004 after launch in September 2003.

== Other aspects ==
Besides the main spacecraft, launched in June 2005, the Cosmos 1 project has funded two other craft:
* A [[sub-orbital spaceflight|suborbital]] test was attempted in 2001 with only two sail blades. The spacecraft failed to separate from the rocket.
* A second orbital spacecraft ([[LightSail-1]]) was launched <ref>{{cite journal|last=Friedman|first=Louis|author-link=Louis Friedman|date=November–December 2009|title=LightSail: A New Way and a New Chance to Fly on Light|journal=The Planetary Report|volume=XXIX|issue=6|pages=4–9|publisher=The Planetary Society|location=Pasadena, California|issn=0736-3680|oclc=7546430}}</ref><ref>{{cite web |url=http://sail.planetary.org/missioncontrol|title=Mission Control Center|publisher=The Planetary Society|access-date=2015-05-22}}</ref> in May 2015.

One of ''Cosmos 1'' solar-sail blades was displayed at the [[Rockefeller Center]] office complex in [[New York City]] in 2003.

== References ==
{{Portal|Spaceflight}}
{{Reflist|30em}}

== External links ==
{{Commons category}}

* [https://web.archive.org/web/20070929115043/http://www.planetary.org/explore/topics/space_missions/private_missions/cosmos1.html ''Cosmos 1'' homepage] at the Planetary Society
* Planetary Society's [http://www.planetary.org/programs/projects/solar_sailing/ solar sail updates and press releases] - current information about the ''Cosmos 2'' follow-on project.
* [http://www.solarsail.org/ ''Cosmos 1'' page] (flash only) from [[Cosmos Studios]]
* {{webarchive|url=https://web.archive.org/web/20070318131355/http://home.earthlink.net/~jbenford/Near-Term_Beam_Sail_2_0.pdf|date=March 18, 2007|title=Near-Term Beamed Sail Propulsion Missions: ''Cosmos 1'' and ''Sun-Diver''}}
* [http://www.nature.com/news/2005/050214/full/433678a.html Space technology: Setting sail for history] (''[[Nature (journal)|Nature]],'' February 16, 2005)
* [https://www.theguardian.com/space/article/0,14493,1426375,00.html Space yacht rides to stars on rays of sunlight] (''[[The Guardian]], ''February 27, 2005)
* [https://www.wired.com/news/space/0,2697,67859,00.html?tw=wn_tophead_1 ''Cosmos 1'' to test solar sail] ([[Wired News]], June 16, 2005)
* [https://web.archive.org/web/20050623002713/http://www.planetary.org/solarsail/animation.html ''Cosmos 1'' videos] (Windows Media, RealPlayer, QuickTime formats)

{{Planetary Society}}
{{Orbital launches in 2005}}

[[Category:Private spaceflight]]
[[Category:Satellite launch failures]]
[[Category:Spacecraft launched in 2005]]
[[Category:Solar sail spacecraft]]
[[Category:The Planetary Society]]
[[Category:Rocket launches in 2005]]