SkySat is a constellation of sub-meter resolution Earth observation satellites owned by Planet Labs, providing imagery, high-definition video and analytics services.[1][2] Planet acquired the satellites with their purchase of Terra Bella (formerly Skybox Imaging), a Mountain View, California-based company founded in 2009 by Dan Berkenstock, Julian Mann, John Fenwick, and Ching-Yu Hu,[3] from Google in 2017.[4]

Overview

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SkySat image of Apple Park taken in May 2017.
 
SkySat off-nadir image of Fitz Roy

The resolution of the SkySat satellite imagery and videos is high enough to observe objects that impact the global economy such as terrain, cars and shipping containers. The satellites can capture video clips lasting up to 90 seconds at 30 frames per second.[5] The high-definition satellite video from SkySat satellites "could help us understand our world better by analyzing movement of goods and people, providing visual data about supply chains, shipping, industrial plant activity, and even humanitarian relief efforts".[5]

The constellation's goal is to be able to provide high-resolution satellite imagery of any place on Earth multiple times a day.[6] When Skybox originally developed the satellites, they planned to "change the nature" of the satellite industry by building satellites with "off-the-shelf" electronics that cost under US$50 million.[7]

History

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By April 2012, Skybox Imaging had raised a total of $91 million (equivalent to about $121M in 2023) of private capital from Khosla Ventures, Bessemer Venture Partners, Canaan Partners and Norwest Venture Partners to develop the SkySat constellation.[6]

On 21 November 2013, the first satellite, SkySat-1, was launched on a Dnepr rocket from Dombarovsky Air Base, Russia.[8] Less than a month later, on 11 December 2013, the first images captured by the SkySat-1 satellite, of Perth, Abu Dhabi, and the coast of Somalia, were released.[9] The second satellite, SkySat-2, launched on a Soyuz-2/Fregat rocket from Baikonur, Kazakhstan on 8 July 2014.[10] The company plans to eventually launch a fleet of 24 satellites.[11] and released its first images within 48 hours of launch.[12]

On 10 February 2014, SSL announced that Skybox had awarded it a contract to build 13 more satellites based on a revised "SkySat C" design.[13][14] The first of these, Skysat-3, also referred to as SkySat-C1, was launched on 22 June 2016 by Indian Space Research Organisation (ISRO) on Polar Satellite Launch Vehicle PSLV-C34.[15][16]

On 10 June 2014, Skybox Imaging announced that it had entered into an agreement to be acquired by Google for $500 million (equivalent to about $644M in 2023).[17][18] The acquisition was completed on 1 August 2014.[18][4] Skybox Imaging changed its name to "Terra Bella" on 8 March 2016, to indicate its focus on image analytics.[19] The new name was partially based on the Terra Bella Avenue in Mountain View, California, where the company's headquarters are located.[20] Terra bella is Italian for "beautiful Earth". The name change was also partially due to perceived trademark infringement that came to light in the Google acquisition.

Four more SkySat units were launched on 16 September 2016, by the Vega rocket's seventh flight from Kourou.[21]

In 2017, Google sold Terra Bella and its SkySat satellite constellation to Planet Labs, adding to their existing fleet of around 50 satellites,[22] for an undisclosed price and entered into a multi-year agreement to purchase SkySat imaging data.[23] Planet Labs launched six more SkySat satellites, along with four Dove CubeSats, on a Minotaur-C rocket from Vandenberg Air Force Base on 31 October 2017.[24][25] An additional two SkySat satellites and three Dove CubeSats were launched on a Falcon 9 rocket from Vandenberg on 3 December 2018.[26][27]

Satellite constellation

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The SkySat satellites are based on the CubeSat concept, using inexpensive automotive grade electronics and fast commercially available processors,[28] but scaled up to approximately the size of a minifridge.[29] The satellites are approximately 80 centimetres (31 in) long, compared to approximately 30 centimetres (12 in) for a 3U CubeSat, and weigh 220 pounds (100 kg).[29]

The first three prototype satellites (SkySat-1, 2 and 3) were produced by Skybox Imaging in-house. SkySats 1 & 2 did not have a propulsion system, SkySat 3 had a propulsion system built by ECAPS in Sweden.[30]

The other 13 satellites are manufactured by SSL,[31] the optical payloads are built by L3 Technologies,[32][25] and the satellite thrusters are provided by ECAPS.[33] The 13 SkySat-C satellites are slightly larger and heavier (with mass about 120 kg or 264 lbs) than the prototypes. They have a planned operational life of 6 years.[34]

The SkySat-C satellites were put on a 500-kilometre (310 mi) Sun-synchronous orbit.[34]

Three of Planet's commercial SkySat (SkySat-16, -17 and -18) Earth-imaging spacecraft launched on top of a stack of 58 SpaceX Starlink-8 satellites on 13 June 2020 aboard a Falcon 9 rocket,[35] and three more (SkySat-19, -20 and -21) hitched a ride on another SpaceX mission on August 18, 2020. Built by Maxar Technologies, each of the SkySat satellites weighs around 110 kilograms (240 lb) at launch. The SkySats are about the size of a mini-refrigerator, and their optical instruments produce images of Earth with a resolution of 50 cm, according to Planet.[36]

List of satellites

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There have been 21 satellites launched.

Name Alt name COSPAR ID Date of launch Rocket Launch site Refs
SkySat-1 2013-066C 21 November 2013 Dnepr Dombarovsky Air Base, Russia [30]
SkySat-2 2014-037D 8 July 2014 Soyuz-2.1b Baikonur, Kazakhstan [30]
SkySat-3 SkySat-C1
SkySat Gen2-1
2016-040C 22 June 2016 PSLV-XL C34 SHAR, Sriharikota, India [34]
SkySat-4 SkySat-C2 2016-058D 16 September 2016 Vega Centre Spatial Guyanais, Kourou [34]
SkySat-5 SkySat-C3 2016-058E 16 September 2016 Vega Centre Spatial Guyanais, Kourou [34]
SkySat-6 SkySat-C4 2016-058B 16 September 2016 Vega Centre Spatial Guyanais, Kourou [34]
SkySat-7 SkySat-C5 2016-058C 16 September 2016 Vega Centre Spatial Guyanais, Kourou [34]
SkySat-8 SkySat-C6 2017-068F 31 October 2017 Minotaur-C 3210 Vandenberg Air Force Base [34]
SkySat-9 SkySat-C7 2017-068E 31 October 2017 Minotaur-C 3210 Vandenberg Air Force Base [34]
SkySat-10 SkySat-C8 2017-068D 31 October 2017 Minotaur-C 3210 Vandenberg Air Force Base [34]
SkySat-11 SkySat-C9 2017-068C 31 October 2017 Minotaur-C 3210 Vandenberg Air Force Base [34]
SkySat-12 SkySat-C10 2017-068B 31 October 2017 Minotaur-C 3210 Vandenberg Air Force Base [34]
SkySat-13 SkySat-C11 2017-068A 31 October 2017 Minotaur-C 3210 Vandenberg Air Force Base [34]
SkySat-14 SkySat-C12 2018-099AR 3 December 2018 Falcon 9 Block 5 Vandenberg Air Force Base [34]
SkySat-15 SkySat-C13 2018-099AW 3 December 2018 Falcon 9 Block 5 Vandenberg Air Force Base [34]
SkySat-16 SkySat-C14 2020-038BL 13 June 2020 Falcon 9 Block 5 Cape Canaveral Air Force Station, SLC-40 [34]
SkySat-17 SkySat-C15 2020-038BM 13 June 2020 Falcon 9 Block 5 Cape Canaveral Air Force Station, SLC-40 [34]
SkySat-18 SkySat-C16 2020-038BN 13 June 2020 Falcon 9 Block 5 Cape Canaveral Air Force Station, SLC-40 [34]
SkySat-19 SkySat-C17 2020-057BQ 18 August 2020 Falcon 9 Block 5 Cape Canaveral Air Force Station, SLC-40 [34]
SkySat-20 SkySat-C18 2020-057BR 18 August 2020 Falcon 9 Block 5 Cape Canaveral Air Force Station, SLC-40 [34]
SkySat-21 SkySat-C19 2020-057BS 18 August 2020 Falcon 9 Block 5 Cape Canaveral Air Force Station, SLC-40 [34]

References

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  1. ^ "Ten things you must know about Isro's record launch of 20 satellites". Hindustan Times. 21 June 2016. Retrieved 5 June 2018.
  2. ^ "Terra Bella Officially Joins Planet". planet.com. Retrieved 18 April 2017.
  3. ^ Perry, Tekla S. (1 May 2013). "Start-up Profile: Skybox Imaging". IEEE Spectrum. Retrieved 12 May 2014.
  4. ^ a b Henry, Caleb (5 August 2014). "Google Closes Skybox Imaging Purchase". Via Satellite. Retrieved 10 August 2014.
  5. ^ a b Wogan, David (30 December 2013). "High-definition video from space is available for purchase finally". Scientific American. Retrieved 12 May 2014.
  6. ^ a b Burns, Matt (17 April 2012). "Skybox Imaging Raises US$70 million To Launch Two High-Resolution Imaging Microsatellites". TechCrunch. Retrieved 12 May 2014.
  7. ^ Truong, Alice (11 December 2013). "Proof That Cheaper Satellites Still Can Take Incredibly Detailed Photos of Earth". Fast Company. Retrieved 12 May 2014.
  8. ^ Clark, Stephen. "Silo-launched Dnepr rocket delivers 32 satellites to space". Website. Spaceflight Now. Retrieved 12 May 2014.
  9. ^ Truong, Alice (11 December 2013). "Proof That Cheaper Satellites Still Can Take Incredibly Detailed Photos Of Earth". Website. Fast Company. Retrieved 11 December 2013.
  10. ^ Hearn, Mark (8 July 2014). "Skybox Imaging successfully launches its SkySat-2 Earth observation satellite". Website. 9to5Google. Retrieved 8 July 2014.
  11. ^ Eisenberg, Anne (10 August 2013). "Microsatellites: What Big Eyes They Have". The New York Times. Retrieved 12 May 2014.
  12. ^ Henry, Caleb (11 July 2014). "Skybox Imaging Releases First Images from SkySat 2". Website. Satellite Today. Retrieved 11 July 2014.
  13. ^ "Skybox Imaging Selects SSL To Build 13 Low Earth Orbit Imaging Satellites". sslmda.com. 10 February 2014. Retrieved 11 August 2016.
  14. ^ "Terra Bella Evaluating Launches for Eight SkySats by 2017". Satellite Today. Access Intelligence. 6 April 2016. Retrieved 11 August 2016.
  15. ^ "SkySat-3 First Light". Terra Bella Blog. Google, Inc. 28 June 2016. Retrieved 11 August 2016.
  16. ^ "International Assortment of Satellites lifted by Indian PSLV Rocket". Spaceflight101.com. 22 June 2016. Retrieved 11 August 2016.
  17. ^ "Alphabet Investor Relations". google.com. 9 June 2014. Retrieved 11 August 2016.
  18. ^ a b "Skybox Imaging + Google". 8 June 2014. Retrieved 29 June 2016.
  19. ^ Lardinois, Frederic (8 March 2016). "Google renames its satellite startup, Skybox Imaging, to Terra Bella and adds focus on image analysis". TechCrunch. AOL Inc. Retrieved 8 March 2016.
  20. ^ Protalinski, Emil (8 March 2016). "Google rebrands Skybox as Terra Bella, will launch "more than a dozen satellites" over the next few years". VentureBeat. Retrieved 8 March 2016.
  21. ^ Clark, Stephen (16 September 2016). "Vega rocket hauls up quintet of Earth observation satellites". Spaceflight Now.
  22. ^ "Google selling Terra Bella satellite imaging business to Planet". TechCrunch. 3 February 2017. Retrieved 12 December 2019.
  23. ^ "Google sells satellite imaging business Terra Bella to Planet Labs". Reuters. 3 February 2017. Retrieved 3 February 2017.
  24. ^ Graham, William (31 October 2017). "Orbital ATK Minotaur-C launches SkySat mission out of Vandenberg". NASASpaceFlight.
  25. ^ a b "Planet Doubles Sub-1 Meter Imaging Capacity With Successful Launch of 6 SkySats". www.planet.com (Press release). Planet Labs Inc.
  26. ^ Safyan, Mike (22 October 2018). "Two SkySat Satellites, Three Doves, and a Record-Breaking Launch on Spaceflight's SSO-A". Planet Labs, Inc.
  27. ^ Wall, Mike (3 December 2018). "SpaceX Rocket Makes Historic 3rd Launch Into Space with 64 Satellites On Board". Space.com.
  28. ^ "High-Performance Satellites". Skybox Imaging. Archived from the original on 17 March 2015. Retrieved 17 March 2017.
  29. ^ a b Samuels, David. "Inside a Startup's Plan to Turn a Swarm of DIY Satellites Into an All-Seeing Eye". Wired. Retrieved 4 November 2017.
  30. ^ a b c "SkySat 1, 2".
  31. ^ "High Resolution Smallsats Built by SSL Arrive at Vandenberg AFB for Launch". sslmda.com (Press release). Space Systems/Loral, LLC. 5 September 2017. Retrieved 1 November 2017.
  32. ^ "REQUEST OF SKYBOX IMAGING, INC. FOR DETERMINATION OF COMPLIANCE WITH SATELLITE IMPLEMENTATION MILESTONES". Federal Communications Commission. 4 March 2013. Retrieved 1 November 2017.
  33. ^ Henry, Caleb (5 August 2016). "Terra Bella's SkySat 3 Green Propulsion System Declared Operational - Via Satellite". Via Satellite. Retrieved 1 November 2017.
  34. ^ a b c d e f g h i j k l m n o p q r s t u "SkySat 3, ..., 21 (SkySat C1, ..., 19)". Gunter's Space Page. 6 June 2013. Retrieved 16 March 2021.
  35. ^ "Launch Schedule". Spaceflight Now. Retrieved 13 June 2020.
  36. ^ https://spaceflightnow.com/2020/06/13/starlink-satellite-deployments-continue-with-successful-falcon-9-launch/ - 15 June 2010
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