A satellite constellation is a group of artificial satellites working together as a system. Unlike a single satellite, a constellation can provide permanent global or near-global coverage, such that at any time everywhere on Earth at least one satellite is visible. Satellites are typically placed in sets of complementary orbital planes and connect to globally distributed ground stations. They may also use inter-satellite communication.
The GPS constellation calls for 24 satellites to be distributed equally among six orbital planes. Notice how the number of satellites in view from a given point on the Earth's surface, in this example at 40°N, changes with time.
satellite series or satellite programs (such as Landsat), which are generations of satellites launched in succession;
satellite fleets, which are groups of satellites from the same manufacturer or operator that function independently from each other (not as a system).
Overview
A bright artificial satellite flare is visible above the Very Large Telescope. Satellite constellations could have an impact on ground-based astronomy.[1]
Satellites in medium Earth orbit (MEO) and low Earth orbit (LEO) are often deployed in satellite constellations, because the coverage area provided by a single satellite only covers a small area that moves as the satellite travels at the high angular velocity needed to maintain its orbit. Many MEO or LEO satellites are needed to maintain continuous coverage over an area. This contrasts with geostationary satellites, where a single satellite, at a much higher altitude and moving at the same angular velocity as the rotation of the Earth's surface, provides permanent coverage over a large area.
For some applications, in particular digital connectivity, the lower altitude of MEO and LEO satellite constellations provide advantages over a geostationary satellite, with lower path losses (reducing power requirements and costs) and latency.[2] The propagation delay for a round-trip internet protocol transmission via a geostationary satellite can be over 600ms, but as low as 125ms for a MEO satellite or 30ms for a LEO system.[3]
There are a large number of constellations that may satisfy a particular mission. Usually constellations are designed so that the satellites have similar orbits, eccentricity and inclination so that any perturbations affect each satellite in approximately the same way. In this way, the geometry can be preserved without excessive station-keeping thereby reducing the fuel usage and hence increasing the life of the satellites. Another consideration is that the phasing of each satellite in an orbital plane maintains sufficient separation to avoid collisions or interference at orbit plane intersections. Circular orbits are popular, because then the satellite is at a constant altitude requiring a constant strength signal to communicate.
A class of circular orbit geometries that has become popular is the Walker Delta Pattern constellation. This has an associated notation to describe it which was proposed by John Walker.[4] His notation is:
i: t/p/f
where:
i is the inclination;
t is the total number of satellites;
p is the number of equally spaced planes; and
f is the relative spacing between satellites in adjacent planes. The change in true anomaly (in degrees) for equivalent satellites in neighbouring planes is equal to f × 360 / t.
For example, the Galileo navigation system is a Walker Delta 56°:24/3/1 constellation. This means there are 24 satellites in 3 planes inclined at 56 degrees, spanning the 360 degrees around the equator. The "1" defines the phasing between the planes, and how they are spaced. The Walker Delta is also known as the Ballard rosette, after A. H. Ballard's similar earlier work.[5][6] Ballard's notation is (t,p,m) where m is a multiple of the fractional offset between planes.
Another popular constellation type is the near-polar Walker Star, which is used by Iridium. Here, the satellites are in near-polar circular orbits across approximately 180 degrees, travelling north on one side of the Earth, and south on the other. The active satellites in the full Iridium constellation form a Walker Star of 86.4°:66/6/2, i.e. the phasing repeats every two planes. Walker uses similar notation for stars and deltas, which can be confusing.
These sets of circular orbits at constant altitude are sometimes referred to as orbital shells.
Several existing satellite constellations typically use a single orbital shell. New large megaconstellations have been proposed that consist of multiple orbital shells.[7][8]
Starlink: first mission (Starlink 0) launched on 24 May 2019; 955 satellites launched, 51 deorbited, 904 in orbit as of 25 November 2020[update]; public beta test in limited latitude range started in November 2020[39]
O3b mPOWER: first 2 satellites launched December 2022; 9 more in 2023–2024, with the initial service start expected in Q3 2023.[40]
^"On the increasing number of satellite constellations". www.eso.org. Retrieved 10 June 2019.
^LEO constellations and tracking challenges Satellite Evolution Group, September 2017, Accessed 26 March 2021
^Real-Time Latency: Rethinking Remote Networks 2021-07-21 at the Wayback Machine Telesat, February 2020, Accessed 26 March 2021
^J. G. Walker, Satellite constellations, Journal of the British Interplanetary Society, vol. 37, pp. 559-571, 1984
^A. H. Ballard, Rosette Constellations of Earth Satellites, IEEE Transactions on Aerospace and Electronic Systems, Vol 16 No. 5, Sep. 1980.
^J. G. Walker, Comments on "Rosette constellations of earth satellites", IEEE Transactions on Aerospace and Electronic Systems, vol. 18 no. 4, pp. 723-724, November 1982.
^ abSPACEX NON-GEOSTATIONARY SATELLITE SYSTEM, Attachment A, TECHNICAL INFORMATION TO SUPPLEMENT SCHEDULE S, US Federal Communications Commission, 8 November 2018, accessed 19 November 2019.
^"Amazon lays out constellation service goals, deployment and deorbit plans to FCC". SpaceNews.com. 2019-07-08. Retrieved 2019-11-22.
^"This is how Elon Musk plans to use SpaceX to give internet to everyone". CNET. 21 February 2018.
^"SpaceX Set to Launch 2 Starlink Satellites to Test Gigabit Broadband". ISPreview. 14 February 2018. Retrieved 10 January 2019.
^"SpaceX's Satellite Internet Service Latency Comes in Under 20 Milliseconds". PCMag UK. 2020-09-09. Retrieved 2020-10-23.
^Thierry Dubois (Dec 19, 2017). "Eight Satellite Constellations Promising Internet Service From Space". Aviation Week & Space Technology.
^The Boeing Company (June 22, 2016). "SAT-LOA-20160622-00058". FCC Space Station Applications. Retrieved February 23, 2018.
^The Boeing Company (June 22, 2016). "SAT-LOA-20161115-00109". FCC Space Station Applications. Retrieved February 23, 2018.
^LeoSat Enterprises. "A NEW TYPE OF SATELLITE CONSTELLATION". Retrieved February 23, 2018.
^"OneWeb asks FCC to authorize 1,200 more satellites". SpaceNews. 2018-03-20. Retrieved 2018-03-23.
^ ab"OneWeb hardware finally coming together". SpaceNews. 3 October 2017. Retrieved 21 October 2018.
^Brodkin, Jon (2019-07-17). "OneWeb's low-Earth satellites hit 400Mbps and 32ms latency in new test". Ars Technica. Retrieved 2020-10-23.
^WorldVu Satellites Limited (April 28, 2016). "ONEWEB NON-GEOSTATIONARY SATELLITE SYSTEM - ATTACHMENT A". FCC Space Station Applications. Retrieved February 23, 2018.
^WorldVu Satellites Limited (April 28, 2016). "SAT-LOI-20160428-00041". FCC Space Station Applications. Retrieved February 23, 2018.
^SES eagerly awaiting the flexibility O3b mPower promises Space News. 11 November 2022. Accessed 3 December 2022
^"Boeing to Build Four Additional 702X Satellites for SES's O3b mPOWER Fleet" (Press release). Boeing. 7 August 2020. Retrieved 29 March 2021.
^SES building a 10-terabit O3b mPower constellation, SpaceNews, 11 September 2017, Accessed 29 March 2021
^"Telesat says ideal LEO constellation is 292 satellites, but could be 512". SpaceNews. 11 September 2018. Retrieved 10 January 2019.
^Telesat Canada (August 24, 2017). "Telesat Technical Narrative". FCC Space Station Applications. Retrieved February 23, 2018.
^Telesat Canada (August 24, 2017). "SAT-PDR-20170301-00023". FCC Space Station Applications. Retrieved February 23, 2018.
^Zhao, Lei (5 March 2018). "Satellite will test plan for communications network". China Daily. Retrieved 20 December 2018.
^Jones, Andrew (13 November 2018). . GBTimes. Archived from the original on 20 December 2018. Retrieved 20 December 2018.
^@EL2squirrel (12 December 2019). "Chinese version of OneWeb: The Hongyan system consists of 864 satellites, with 8Tbps of bandwidth, Orbital altitude 1175km" (Tweet). Retrieved 16 December 2019 – via Twitter.
^Jewett, Rachel (31 March 2022). "Hanwha Systems Plans 2,000-Satellite LEO Constellation for Mobility Applications". Via Satellite. Retrieved 12 July 2022.
^Porter, Jon (2019-04-04). "Amazon will launch thousands of satellites to provide internet around the world". The Verge. Retrieved 2019-11-17.
^"Boeing wants to help OneWeb satellite plans". Advanced Television. 2017-12-17. Retrieved 2018-10-21.
^"LeoSat, absent investors, shuts down". Space News.
^"OneWeb increases mega-constellation to 74 satellites". 2020-03-21. Retrieved 2020-04-07.
^"Coronavirus: OneWeb blames pandemic for collapse". 2020-03-30. Retrieved 2020-04-07.
^"Voluntary Petition for Non-Individuals Filing for Bankruptcy" (PDF). Omni Agent Solutions. 2020-03-27. Retrieved 2020-04-07.
^Samantha Mathewson (6 November 2020). "SpaceX opens Starlink satellite internet to public beta testers: report".
^SpaceX launches first pair of O3b mPower satellites SpaceNews. 16 December 2022. Accessed 27 December 2022
^Barbosa, Rui C. (21 December 2018). "Chinese Long March 11 launches with the first Hongyun satellite". NASASpaceFlight.com. Retrieved 24 December 2018.
^Barbosa, Rui (29 December 2018). "Long March 2D concludes 2018 campaign with Hongyan-1 launch". NASASpaceFlight.com. Retrieved 29 December 2018.
^@Cosmic_Penguin (14 December 2019). "Notice that these satellites from CASC are mentioned as part of a "national satellite Internet system". There are rumors that several of the planned Chinese private LEO comsat constellations have been recently absorbed into one big nationalized one" (Tweet). Retrieved 16 December 2019 – via Twitter.
External links
Wikimedia Commons has media related to Satellite constellations.
Satellite constellation simulation tools:
AVM Dynamics Satellite Constellation Modeler
SaVi Satellite Constellation Visualization
Transfinite Visualyse Professional
More information:
Internetworking with satellite constellations - a PhD thesis (2001)
Lloyd's satellite constellations - last updated 20 July 2011
Examination and analysis of polar low Earth orbit constellation-IEEE
May 19, 2023
satellite, constellation, satellite, constellation, group, artificial, satellites, working, together, system, unlike, single, satellite, constellation, provide, permanent, global, near, global, coverage, such, that, time, everywhere, earth, least, satellite, v. A satellite constellation is a group of artificial satellites working together as a system Unlike a single satellite a constellation can provide permanent global or near global coverage such that at any time everywhere on Earth at least one satellite is visible Satellites are typically placed in sets of complementary orbital planes and connect to globally distributed ground stations They may also use inter satellite communication The GPS constellation calls for 24 satellites to be distributed equally among six orbital planes Notice how the number of satellites in view from a given point on the Earth s surface in this example at 40 N changes with time Contents 1 Other satellite groups 2 Overview 3 Design 3 1 Walker Constellation 4 Orbital shell 5 List of satellite constellations 5 1 Navigational satellite constellations 5 2 Communications satellite constellations 5 2 1 Broadcasting 5 2 2 Monitoring 5 2 3 Internet access 5 3 Earth observation satellite constellations 6 See also 7 Notes 8 References 9 External linksOther satellite groups EditSatellite constellations should not be confused with satellite clusters which are groups of satellites moving very close together in almost identical orbits see satellite formation flying satellite series or satellite programs such as Landsat which are generations of satellites launched in succession satellite fleets which are groups of satellites from the same manufacturer or operator that function independently from each other not as a system Overview Edit A bright artificial satellite flare is visible above the Very Large Telescope Satellite constellations could have an impact on ground based astronomy 1 Satellites in medium Earth orbit MEO and low Earth orbit LEO are often deployed in satellite constellations because the coverage area provided by a single satellite only covers a small area that moves as the satellite travels at the high angular velocity needed to maintain its orbit Many MEO or LEO satellites are needed to maintain continuous coverage over an area This contrasts with geostationary satellites where a single satellite at a much higher altitude and moving at the same angular velocity as the rotation of the Earth s surface provides permanent coverage over a large area For some applications in particular digital connectivity the lower altitude of MEO and LEO satellite constellations provide advantages over a geostationary satellite with lower path losses reducing power requirements and costs and latency 2 The propagation delay for a round trip internet protocol transmission via a geostationary satellite can be over 600 ms but as low as 125 ms for a MEO satellite or 30 ms for a LEO system 3 Examples of satellite constellations include the Global Positioning System GPS Galileo and GLONASS constellations for navigation and geodesy in MEO the Iridium and Globalstar satellite telephony services and Orbcomm messaging service in LEO the Disaster Monitoring Constellation and RapidEye for remote sensing in sun synchronous LEO Russian Molniya and Tundra communications constellations in highly elliptic orbit and satellite broadband constellations under construction from Starlink and OneWeb in LEO and operational from O3b in MEO Design EditWalker Constellation Edit There are a large number of constellations that may satisfy a particular mission Usually constellations are designed so that the satellites have similar orbits eccentricity and inclination so that any perturbations affect each satellite in approximately the same way In this way the geometry can be preserved without excessive station keeping thereby reducing the fuel usage and hence increasing the life of the satellites Another consideration is that the phasing of each satellite in an orbital plane maintains sufficient separation to avoid collisions or interference at orbit plane intersections Circular orbits are popular because then the satellite is at a constant altitude requiring a constant strength signal to communicate A class of circular orbit geometries that has become popular is the Walker Delta Pattern constellation This has an associated notation to describe it which was proposed by John Walker 4 His notation is i t p fwhere i is the inclination t is the total number of satellites p is the number of equally spaced planes and f is the relative spacing between satellites in adjacent planes The change in true anomaly in degrees for equivalent satellites in neighbouring planes is equal to f 360 t For example the Galileo navigation system is a Walker Delta 56 24 3 1 constellation This means there are 24 satellites in 3 planes inclined at 56 degrees spanning the 360 degrees around the equator The 1 defines the phasing between the planes and how they are spaced The Walker Delta is also known as the Ballard rosette after A H Ballard s similar earlier work 5 6 Ballard s notation is t p m where m is a multiple of the fractional offset between planes Another popular constellation type is the near polar Walker Star which is used by Iridium Here the satellites are in near polar circular orbits across approximately 180 degrees travelling north on one side of the Earth and south on the other The active satellites in the full Iridium constellation form a Walker Star of 86 4 66 6 2 i e the phasing repeats every two planes Walker uses similar notation for stars and deltas which can be confusing These sets of circular orbits at constant altitude are sometimes referred to as orbital shells Orbital shell EditIn spaceflight an orbital shell is a set of artificial satellites in circular orbits at a certain fixed altitude 7 In the design of satellite constellations an orbital shell usually refers to a collection of circular orbits with the same altitude and oftentimes orbital inclination distributed evenly in celestial longitude and mean anomaly citation needed For a sufficiently high inclination and altitude the orbital shell covers the entire orbited body In other cases the coverage extends up to a certain maximum latitude citation needed Several existing satellite constellations typically use a single orbital shell New large megaconstellations have been proposed that consist of multiple orbital shells 7 8 List of satellite constellations EditNavigational satellite constellations Edit Main article Satellite navigation Satellite constellations used for navigation Name Operator Satellites and orbits latest design excluding spares Coverage Services Status Years in serviceGlobal Positioning System GPS USSF 24 in 6 planes at 20 180 km 55 MEO Global Navigation Operational 1993 presentGLONASS Roscosmos 24 in 3 planes at 19 130 km 64 8 MEO Global Navigation Operational 1995 presentGalileo EUSPA ESA 24 in 3 planes at 23 222 km 56 MEO Global Navigation Operational 2019 presentBeiDou CNSA 3 geostationary at 35 786 km GEO 3 in 3 planes at 35 786 km 55 GSO 24 in 3 planes at 21 150 km 55 MEO Global Navigation Operational 2012 present Asia2018 present globallyNAVIC ISRO 3 geostationary at 35 786 km GEO 4 in 2 planes at 250 24 000 km 29 GSO Regional Navigation Operational 2018 presentQZSS JAXA 1 geostationary at 35 786 km GEO 3 in 3 planes at 32 600 39 000 43 GSO Regional Navigation Operational 2018 presentCommunications satellite constellations Edit See also Satellite communication and Category Communications satellite constellations Broadcasting Edit Sirius Satellite Radio XM Satellite Radio Othernet Molniya discontinued Monitoring Edit Spire AIS ADS B Iridium AIS ADS B IoT Myriota IoT Swarm Technologies IoT Astrocast IoT TDRSSInternet access Edit Operational communications satellite constellations Name Operator Constellation design Coverage Freq ServicesBroadband Global Area Network BGAN Inmarsat 3 geostationary satellites 82 S to 82 N Internet accessGlobal Xpress GX Inmarsat 5 Geostationary satellites 9 Ka band Internet accessGlobalstar Globalstar 48 at 1400 km 52 8 planes 10 70 S to 70 N 10 Internet access satellite telephonyIridium Iridium Communications 66 at 780 km 86 4 6 planes Global L bandKa band Internet access satellite telephonyO3b SES S A 20 at 8 062 km 0 circular equatorial orbit 45 S to 45 N Ka band Internet accessOrbcomm ORBCOMM 17 at 750 km 52 OG2 65 S to 65 N IoT and M2M communication AISDefense Satellite Communications System DSCS 4th Space Operations Squadron Military communicationsWideband Global SATCOM WGS 4th Space Operations Squadron 10 geostationary satellites Military communicationsViaSat Viasat Inc 4 geostationary satellites Varying Internet accessEutelsat Eutelsat 20 geostationary satellites CommercialThuraya Thuraya 2 geostationary satellites EMEA and Asia L band Internet access satellite telephonyStarlink SpaceX LEO in several orbital shells 1000 satellites at 550 km Feb 2021 12000 satellites at 350 550 km planned 44 S to 52 N Feb 2021 Global planned Ku 12 18 GHz Ka 26 5 40 GHz Internet access 11 12 13 Some systems were proposed but never realised Abandoned communication satellite constellation designs Name Operator Constellation design Freq Services StatusCelestri Motorola 63 satellites at 1400 km 48 7 planes Ka band 20 30 GHz Global low latency broadband Internet services Abandoned in May 1998Teledesic Teledesic 840 satellites at 700 km 98 2 21 planes 1994 design 288 satellites at 1400 km 98 2 12 planes 1997 design Ka band 20 30 GHz 100 Mbit s up 720 Mbit s down global internet access Abandoned in October 2002Other Internet access systems are proposed or currently being developed Proposed internet satellite constellations 14 Constellation Manufacturer Number Weight Unveil Avail Altitude Offer Band Inter sat linksBoeing Boeing Satellite 1 396 2 956 2016 1 200 km745 mi Broadband V 40 75 GHz None 15 16 LeoSat Thales Alenia 78 108 1 250 kg2 755 lb 2015 2022 1 400 km895 mi 100 Mbit s increments Ka 26 5 40 GHz Optical 17 OneWeb constellation OneWeb and Airbus JV 882 1980 18 145 kg320 lb 2015 2020 19 1 200 km745 mi Up to 595 Mbit s 19 with 32 ms latency 20 Ku 12 18 GHz Ka 26 5 40 GHz None 21 22 O3b mPOWER SES S A Boeing 11 1700 kg 2017 Q3 2023 23 8 000 km4 970 mi 50 Mbit s 10 Gbit s each user 24 25 45 S to 45 N Ka 26 5 40 GHz NoneTelesat LEO Airbus SSTLSS Loral a 117 512 26 2016 2021 1 000 1 248 km621 775 mi Fiber optic cable like Ka 26 5 40 GHz Optical 27 28 Hongyun 29 CASIC 156 2017 2022 160 2 000 km99 1 243 miHongyan 30 CASC 320 864 31 2017 2023 1 100 1 175 km684 730 miHanwha Systems 32 2000 2022 2025Project Kuiper Amazon 3236 2019 590 630 km370 390 mi 56 S to 56 N 33 first two prototypes ProgressBoeing Satellite is transferring the application to OneWeb 34 LeoSat shut down completely in 2019 35 The OneWeb constellation had 6 pilot satellites in February 2019 74 satellites launched as of 21 March 2020 36 but filed for bankruptcy on 27 March 2020 37 38 Starlink first mission Starlink 0 launched on 24 May 2019 955 satellites launched 51 deorbited 904 in orbit as of 25 November 2020 update public beta test in limited latitude range started in November 2020 39 O3b mPOWER first 2 satellites launched December 2022 9 more in 2023 2024 with the initial service start expected in Q3 2023 40 Telesat LEO two prototypes 2018 launch CASIC Hongyun prototype launched in December 2018 41 CASC Hongyan prototype launched in December 2018 42 might be merged with Hongyun 43 Project Kuiper FCC filing in July 2019Earth observation satellite constellations Edit See also List of Earth observation satellites RADARSAT Constellation Planet Labs Pleiades 1A and 1B Satellogic RapidEye Disaster Monitoring Constellation A train SPOT 6 and SPOT 7 SpireSee also Edit Wikisource has original text related to this article Satellite constellations Satellite internet constellation Light pollution Types of geocentric orbit Orbital mechanicsNotes EditReferences Edit On the increasing number of satellite constellations www eso org Retrieved 10 June 2019 LEO constellations and tracking challenges Satellite Evolution Group September 2017 Accessed 26 March 2021 Real Time Latency Rethinking Remote Networks Archived 2021 07 21 at the Wayback Machine Telesat February 2020 Accessed 26 March 2021 J G Walker Satellite constellations Journal of the British Interplanetary Society vol 37 pp 559 571 1984 A H Ballard Rosette Constellations of Earth Satellites IEEE Transactions on Aerospace and Electronic Systems Vol 16 No 5 Sep 1980 J G Walker Comments on Rosette constellations of earth satellites IEEE Transactions on Aerospace and Electronic Systems vol 18 no 4 pp 723 724 November 1982 a b SPACEX NON GEOSTATIONARY SATELLITE SYSTEM Attachment A TECHNICAL INFORMATION TO SUPPLEMENT SCHEDULE S US Federal Communications Commission 8 November 2018 accessed 19 November 2019 Amazon lays out constellation service goals deployment and deorbit plans to FCC SpaceNews com 2019 07 08 Retrieved 2019 11 22 Land Xpress Retrieved 1 November 2021 a b Globalstar satellites www n2yo com Retrieved 2019 11 22 This is how Elon Musk plans to use SpaceX to give internet to everyone CNET 21 February 2018 SpaceX Set to Launch 2 Starlink Satellites to Test Gigabit Broadband ISPreview 14 February 2018 Retrieved 10 January 2019 SpaceX s Satellite Internet Service Latency Comes in Under 20 Milliseconds PCMag UK 2020 09 09 Retrieved 2020 10 23 Thierry Dubois Dec 19 2017 Eight Satellite Constellations Promising Internet Service From Space Aviation Week amp Space Technology The Boeing Company June 22 2016 SAT LOA 20160622 00058 FCC Space Station Applications Retrieved February 23 2018 The Boeing Company June 22 2016 SAT LOA 20161115 00109 FCC Space Station Applications Retrieved February 23 2018 LeoSat Enterprises A NEW TYPE OF SATELLITE CONSTELLATION Retrieved February 23 2018 OneWeb asks FCC to authorize 1 200 more satellites SpaceNews 2018 03 20 Retrieved 2018 03 23 a b OneWeb hardware finally coming together SpaceNews 3 October 2017 Retrieved 21 October 2018 Brodkin Jon 2019 07 17 OneWeb s low Earth satellites hit 400Mbps and 32ms latency in new test Ars Technica Retrieved 2020 10 23 WorldVu Satellites Limited April 28 2016 ONEWEB NON GEOSTATIONARY SATELLITE SYSTEM ATTACHMENT A FCC Space Station Applications Retrieved February 23 2018 WorldVu Satellites Limited April 28 2016 SAT LOI 20160428 00041 FCC Space Station Applications Retrieved February 23 2018 SES eagerly awaiting the flexibility O3b mPower promises Space News 11 November 2022 Accessed 3 December 2022 Boeing to Build Four Additional 702X Satellites for SES s O3b mPOWER Fleet Press release Boeing 7 August 2020 Retrieved 29 March 2021 SES building a 10 terabit O3b mPower constellation SpaceNews 11 September 2017 Accessed 29 March 2021 Telesat says ideal LEO constellation is 292 satellites but could be 512 SpaceNews 11 September 2018 Retrieved 10 January 2019 Telesat Canada August 24 2017 Telesat Technical Narrative FCC Space Station Applications Retrieved February 23 2018 Telesat Canada August 24 2017 SAT PDR 20170301 00023 FCC Space Station Applications Retrieved February 23 2018 Zhao Lei 5 March 2018 Satellite will test plan for communications network China Daily Retrieved 20 December 2018 Jones Andrew 13 November 2018 China to launch first Hongyan LEO communications constellation satellite soon GBTimes Archived from the original on 20 December 2018 Retrieved 20 December 2018 EL2squirrel 12 December 2019 Chinese version of OneWeb The Hongyan system consists of 864 satellites with 8Tbps of bandwidth Orbital altitude 1175km Tweet Retrieved 16 December 2019 via Twitter Jewett Rachel 31 March 2022 Hanwha Systems Plans 2 000 Satellite LEO Constellation for Mobility Applications Via Satellite Retrieved 12 July 2022 Porter Jon 2019 04 04 Amazon will launch thousands of satellites to provide internet around the world The Verge Retrieved 2019 11 17 Boeing wants to help OneWeb satellite plans Advanced Television 2017 12 17 Retrieved 2018 10 21 LeoSat absent investors shuts down Space News OneWeb increases mega constellation to 74 satellites 2020 03 21 Retrieved 2020 04 07 Coronavirus OneWeb blames pandemic for collapse 2020 03 30 Retrieved 2020 04 07 Voluntary Petition for Non Individuals Filing for Bankruptcy PDF Omni Agent Solutions 2020 03 27 Retrieved 2020 04 07 Samantha Mathewson 6 November 2020 SpaceX opens Starlink satellite internet to public beta testers report SpaceX launches first pair of O3b mPower satellites SpaceNews 16 December 2022 Accessed 27 December 2022 Barbosa Rui C 21 December 2018 Chinese Long March 11 launches with the first Hongyun satellite NASASpaceFlight com Retrieved 24 December 2018 Barbosa Rui 29 December 2018 Long March 2D concludes 2018 campaign with Hongyan 1 launch NASASpaceFlight com Retrieved 29 December 2018 Cosmic Penguin 14 December 2019 Notice that these satellites from CASC are mentioned as part of a national satellite Internet system There are rumors that several of the planned Chinese private LEO comsat constellations have been recently absorbed into one big nationalized one Tweet Retrieved 16 December 2019 via Twitter External links Edit Wikimedia Commons has media related to Satellite constellations Satellite constellation simulation tools AVM Dynamics Satellite Constellation Modeler SaVi Satellite Constellation Visualization Transfinite Visualyse ProfessionalMore information Internetworking with satellite constellations a PhD thesis 2001 Lloyd s satellite constellations last updated 20 July 2011 Examination and analysis of polar low Earth orbit constellation IEEE Retrieved from https en wikipedia org w index php title Satellite constellation amp oldid 1154452741, wikipedia, wiki, book, books, library,
