Sunjammer (spacecraft)

Sunjammer
Sunjammer as seen from the top of the vacuum chamber where it was tested.
NamesSolar Sail Demonstrator
Mission typeTechnology demonstration
OperatorNASA
WebsiteThe Sunjammer Project
Spacecraft properties
ManufacturerLGarde
Launch mass32 kg (71 lb)
Dimensions38 m × 38 m (125 ft × 125 ft)
Start of mission
Launch dateCanceled
(planned for January 2015)
RocketFalcon 9
Launch siteCape Canaveral Air Force Station
ContractorSpaceX
Orbital parameters
Reference systemGeocentric orbit (planned)
RegimeLow Earth orbit

Sunjammer (Solar Sail Demonstrator) was a NASA mission intended to demonstrate a solar sail constructed by LGarde, but was canceled before launch. The largest solar sail made as of 2013, Sunjammer was named after a 1964 [1] Arthur C. Clarke story of the same name, Sunjammer, in which several solar sails compete in a race to the Moon.[2] Sunjammer was slated to launch in January 2015 as the secondary payload of a SpaceX Falcon 9 launch vehicle, along with the Earth observation satellite DSCOVR.[2] Citing a lack of confidence in its contractor's ability to deliver, the mission was canceled in October 2014.[3]

Spacecraft design

Constructed of Kapton in order to withstand the extreme temperatures of space, Sunjammer has a width and height of 38 m (125 ft), giving it a total surface area of over 1,200 m2 (13,000 sq ft) and making it the largest solar sail as of 2013.[4] Despite its huge surface area, Sunjammer has a thickness of only 5 μm, giving it an extremely low weight of about 32 kg (71 lb) and allowing it to be stored in a space the size of a dishwasher.[4] Once in space, the large surface area of the solar sail would allow it to achieve a thrust of about 0.01 N[5] and a characteristic acceleration of about 0.25 mm/s2.[6] To control its orientation, and via this its speed and direction, Sunjammer was to use gimballed vanes (each of which is itself a small solar sail) located at the tips of each of its 4 booms, instead of thrusters, eliminating the need for any propellant other than the rays of the Sun.[5]

In addition to being a demonstration craft, Sunjammer was to collect scientific data in its own right. With several instruments to detect various aspects of space weather, Sunjammer could have eventually become part of a larger network of solar sails studying the Sun, allowing for the creation of a more robust early-warning system for space weather.[2]


Mission

Prior to its cancellation, Sunjammer was slated for launch in January 2015 aboard a Falcon 9 launch vehicle, a slight delay from an earlier projection of November 2014. It was to launch as a secondary payload along with the primary DSCOVR Earth observation and space weather satellite.[2] Within two months of launch the spacecraft was to test various technologies, such as deployment, vector control via altitude vanes, and eventually reaching a location near the Earth-Sun L1 Lagrange point.[4]

Payloads

Sunjammer was to carry two British space science payloads: the Solar Wind Analyser (SWAN) developed by the Mullard Space Science Laboratory of University College London,[7] and the MAGIC magnetometer developed by the Blackett Laboratory of Imperial College London.[8][9]

Sunjammer was to carry a Celestis Memorial Spaceflight payload of cremated remains.[10]

See also

References

  1. ^ "Short Stories". Arthur C. Clarke. Archived from the original on 2 October 2011. Retrieved 14 June 2013.
  2. ^ a b c d "World's Largest Solar Sail to Launch in November 2014". Space.com. 13 June 2013. Retrieved 14 June 2013.
  3. ^ Leone, Dan (17 October 2014). "NASA Nixes Sunjammer Mission, Cites Integration, Schedule Risk". SpaceNews. Archived from the original on 18 October 2014.
  4. ^ a b c David, Leonard (31 January 2013). "World's Largest Solar Sail to Launch in November 2014". Space.com. Retrieved 15 June 2013.
  5. ^ a b "Solar Sail Demonstration (The Sunjammer Project)". Technology Demonstration Missions. NASA. 16 December 2011. Retrieved 15 June 2013. Public Domain This article incorporates text from this source, which is in the public domain.
  6. ^ Barnes, Nathan C.; Derbes, William C.; Player, Charles J.; Diedrich, Benjamin L. (2014), Macdonald, Malcolm (ed.), "Sunjammer: A Solar Sail Demonstration", Advances in Solar Sailing, Berlin, Heidelberg: Springer Berlin Heidelberg, pp. 115–126, doi:10.1007/978-3-642-34907-2_8, hdl:2060/20120015305, ISBN 978-3-642-34906-5, retrieved 1 January 2023
  7. ^ "Sunjammer team to present latest solar sail technology". Archived from the original on 13 December 2013. Retrieved 8 August 2013.
  8. ^ "Dr. Jonathan Eastwood, Imperial College London". Archived from the original on 16 May 2014. Retrieved 8 August 2013.
  9. ^ Sunjammer spacecraft to 'sail' towards the sun - Telegraph
  10. ^ "SUNJAMMER MISSION PARTNERS ANNOUNCED for GIANT NASA SOLAR SAIL LAUNCH" (PDF). sunjammermission.com Press Release. 4 June 2013. Archived from the original (PDF) on 9 September 2013.