Starlink
Starlink is a satellite internet constellation operated by SpaceX providing satellite Internet access coverage to most of the Earth. The constellation has grown to over 1,700 satellites through 2021, and will eventually consist of many thousands of mass-produced small satellites in low Earth orbit (LEO), which communicate with designated ground transceivers. While the technical possibility of satellite internet service covers most of the global population, actual service can be delivered only in countries that have licensed SpaceX to provide service within any specific national jurisdiction. As of February 2022, the beta internet service offering is available in 29 countries.

The SpaceX satellite development facility in Redmond, Washington, houses the Starlink research, development, manufacturing, and orbit control teams. The cost of the decade-long project to design, build, and deploy the constellation was estimated by SpaceX in May 2018 to be at least US$10 billion.. In February 2017, documents indicated that SpaceX expects more than US$30 billion in revenue by 2025 from its satellite constellation, while revenues from its launch business were expected to reach US$5 billion in the same year.

On 15 October 2019, the United States Federal Communications Commission (FCC) submitted filings to the International Telecommunication Union (ITU) on SpaceX's behalf to arrange spectrum for 30,000 additional Starlink satellites to supplement the 12,000 Starlink satellites already approved by the FCC. 

Astronomers have raised concerns about the constellations' effect on ground-based astronomy and how the satellites will add to an already congested orbital environment. SpaceX has attempted to mitigate astronomy concerns by implementing several upgrades to Starlink satellites aimed at reducing their brightness during operation. The satellites are equipped with krypton-fueled Hall thrusters which allow them to de-orbit at the end of their life. Additionally, the satellites are designed to autonomously avoid collisions based on uplinked tracking data.

History

Early planning 
Large constellations of low Earth orbit satellites were first conceptualized in the mid-1980s as part of the Strategic Defense Initiative. These technologies led to numerous commercial megaconstellations planned in the 1990s such as Celestri, Teledesic, Iridium and Globalstar. However all entities entered bankruptcy by the dot-com bubble burst, due in part to excessive launch costs at the time. 

In June 2004, the newly formed company SpaceX acquired a stake in Surrey Satellite Technology (SSTL) as part of a “shared strategic vision”. SSTL was at that time working to extend the Internet into space. However, SpaceX’s stake was eventually sold back to EADS Astrium in 2008 after the company became more focused on navigation and Earth observation.

In early 2014, Elon Musk and Greg Wyler were reportedly working together planning a constellation of around 700 satellites called WorldVu, which would be over 10 times the size of the then largest Iridium satellite constellation. However, these discussions broke down by June 2014, and Elon’s company SpaceX instead stealthily filed an ITU application via the Norway telecom regulator under the name STEAM. SpaceX confirmed the connection in the 2016 application to license Starlink with the FCC.

2015–2017 

Starlink was publicly announced in January 2015 with the opening of the SpaceX satellite development facility in Redmond, WA. During the opening, Elon Musk stated there is still significant unmet demand worldwide for low-cost broadband capabilities. and that Starlink would target bandwidth to carry up to 50% of all backhaul communications traffic, and up to 10% of local Internet traffic, in high-density cities.  

At the time, the Seattle-area office planned to initially hire approximately 60 engineers, and potentially 1,000 people by 2018. The company operated in  of leased space by late 2016, and by January 2017 had taken on a  second facility, both in Redmond. In August 2018, SpaceX consolidated all their Seattle-area operations with a move to a larger three-building facility at Redmond Ridge Corporate Center to support satellite manufacturing in addition to R&D.

In July 2016, SpaceX acquired a  creative space in Irvine, California (Orange County). SpaceX job listings indicated the Irvine office would include signal processing, RFIC, and ASIC development for the satellite program.

By January 2016, the company had publicly disclosed plans to have two prototype satellites flying in 2016, and to have the initial satellite constellation in orbit and operational by approximately 2020.

By October 2016, the satellite division was focusing on a significant business challenge of achieving a sufficiently low-cost design for the user equipment, aiming for something that ostensibly can be installed easily at end-user premises for approximately US$200. Overall, SpaceX President Gwynne Shotwell said then that the project remained in the "design phase as the company seeks to tackle issues related to user-terminal cost". Deployment of the constellation was not then projected until "late in this decade or early in the next".

In November 2016, SpaceX filed an application with the Federal Communications Commission (FCC) for a "non-geostationary orbit (NGSO) satellite system in the Fixed-Satellite Service using the Ku- and Ka- frequency bands".

SpaceX trademarked the name Starlink for their satellite broadband network in 2017; the name was inspired by the book The Fault in Our Stars.

In March 2017, SpaceX filed plans with the FCC to field a second orbital shell of more than 7,500 "V-band satellites in non-geosynchronous orbits to provide communications services" in an electromagnetic spectrum that has not previously been heavily employed for commercial communications services. Called the "Very-Low Earth Orbit (VLEO) constellation", it would comprise 7,518 satellites and would orbit at just  altitude, while the smaller, originally planned group of 4,425 satellites would operate in the Ka- and Ku-bands and orbit at  altitude.

The first two test satellites built were not flown but were used in ground testing. The planned launch of two revised test satellites was then moved to 2018.

Some controversy arose in 2015–2017 with regulatory authorities on licensing of the communications spectrum for these large constellations of satellites. The traditional and historical regulatory rule for the licensing spectrum has been that satellite operators could "launch a single spacecraft to meet their in-service deadline [from the regulator], a policy is seen as allowing an operator to block the use of valuable radio spectrum for years without deploying its fleet". On 17 December 2015, the FCC set a six-year deadline to have an entire large constellation deployed to comply with licensing terms. This rule was loosened up on 7 September 2017, as FCC decided that half of the constellation must be in orbit within six years, while the full system should be in orbit within nine years from the date of the license.

SpaceX filed documents in late 2017 with the Federal Communications Commission (FCC) to clarify their space debris mitigation plan, under which the company was to:
"...implement an operations plan for the orderly de-orbit of satellites nearing the end of their useful lives (roughly five to seven years) at a rate far faster than is required under international standards. [Satellites] will de-orbit by propulsively moving to a disposal orbit from which they will re-enter the Earth's atmosphere within approximately one year after completion of their mission."

2018–2019 

In March 2018, the FCC granted SpaceX approval for the initial 4,425 satellites, with some conditions. SpaceX would need to obtain a separate approval from the International Telecommunication Union (ITU). The FCC supported a NASA request to ask SpaceX to achieve an even higher level of de-orbiting reliability than the standard that NASA had previously used for itself: reliably de-orbiting 90% of the satellites after their missions are complete.

In May 2018, SpaceX expected the total cost of development and buildout of the constellation to approach US$10 billion. In mid-2018, SpaceX reorganized the satellite development division in Redmond, and terminated several members of senior management.

In November 2018, SpaceX received U.S. regulatory approval to deploy 7,518 broadband satellites, in addition to the 4,425 approved earlier. SpaceX's initial 4,425 satellites had been requested in the 2016 regulatory filings to orbit at altitudes of  to , well above the International Space Station. The new approval was for the addition of a very-low Earth orbit non-geostationary satellite orbit constellation, consisting of 7,518 satellites operating at altitudes from  to , below the ISS. Also in November 2018, SpaceX made new regulatory filings with the U.S. Federal Communications Commission (FCC) to request the ability to alter its previously granted license in order to operate approximately 1,600 of the 4,425 Ka-/Ku-band satellites approved for operation at  in a "new lower shell of the constellation" at only  orbital altitude. These satellites would effectively operate in a third orbital shell, a  orbit, while the higher and lower orbits at approximately  and approximately  would be used only later, once a considerably larger deployment of satellites becomes possible in the later years of the deployment process. The FCC approved the request in April 2019, giving approval to place nearly 12,000 satellites in three orbital shells: initially approximately 1,600 in a  - altitude shell, and subsequently placing approximately 2,800 Ku- and Ka-band spectrum satellites at  and approximately 7,500 V-band satellites at .

With plans by several providers to build commercial space-Internet mega-constellations of thousands of satellites increasingly likely to become a reality, the U.S. military began to perform test studies in 2018 to evaluate how the networks might be used. In December 2018, the U.S. Air Force issued a US$28 million contract for specific test services on Starlink.

In February 2019, a sister company of SpaceX, SpaceX Services Inc., filed a request with the FCC to receive a license for the operation of up to a million fixed satellite Earth stations that would communicate with its non-geostationary orbit (NGSO) satellite Starlink system.

SpaceX's plans in 2019 were for the initial 12,000 satellites to orbit in three orbital shells:

 First shell: 1,440 in a  altitude shell
 Second shell: 2,825 Ku-band and Ka-band spectrum satellites at 
 Third shell: 7,500 V-band satellites at 

In total, nearly 12,000 satellites were planned to be deployed, with (as of 2019) a possible later extension to 42,000.

By April 2019, SpaceX was transitioning their satellite efforts from research and development to manufacturing, with the planned first launch of a large group of satellites to orbit, and the clear need to achieve an average launch rate of "44 high-performance, low-cost spacecraft built and launched every month for the next 60 months" to get the 2,200 satellites launched to support their FCC spectrum allocation license assignment. SpaceX said they will meet the deadline of having half the constellation "in orbit within six years of authorization... and the full system in nine years".

By the end of June 2019, SpaceX had communicated with all 60 satellites but lost contact with three; the remaining 57 worked as intended. Forty-five satellites had reached their final orbital altitude of , five were still raising their orbits, and another five were undergoing systems checks before they raise their orbits. The remaining two satellites were intended to be quickly removed from orbit and re-enter the atmosphere in order to test the satellite de-orbiting process; the three that lost contact were also expected to re-enter, but will do so passively from atmospheric drag as SpaceX was no longer able to actively control them.

In June 2019, SpaceX applied to the FCC for a license to test up to 270 ground terminals – 70 nationwide across the United States and 200 in Washington state at SpaceX employee homes – and aircraft-borne antenna operation from four distributed United States airfields; as well as five ground-to-ground test locations.

By September 2019, SpaceX had gone back to the FCC to apply for more changes to the orbital constellation. SpaceX asked to triple the number of orbital planes in the  orbital shell, from 24 to 72, arguing that they could then place satellites into multiple planes from a single launch. SpaceX argued that this change could bring coverage to the southern United States in time for the 2020 hurricane season. The change was approved in December 2019, and will now see only 22 satellites in each plane rather than the 66 that had been a part of the original design. The total number of satellites in the 550 km shell would remain the same, at around 1,600.

In October 2019, Elon Musk publicly tested the Starlink network by using an Internet connection routed through the network to post a first tweet to social media site Twitter.

2020–2022 

, SpaceX has launched 2,091 Starlink satellites, including demo satellites Tintin A and B. They continue to launch up to 60 more per Falcon 9 flight, with launches as often as every two weeks in 2021.

In April 2020, SpaceX modified the architecture of the Starlink network. SpaceX submitted an application to the Federal Communications Commission (FCC) proposing to operate more satellites in lower orbits in the first phase than the FCC previously authorized. The first phase will still include 1,440 satellites in the first shell orbiting at  in planes inclined 53.0°, with no change to the first shell of the constellation launched largely in 2020.

 First shell: 1,440 in a  altitude shell at 53.0° inclination
 Second shell: 1,440 in a  shell at 53.2° inclination
 Third shell: 720 in a  shell at 70° inclination
 Fourth shell: 336 in a  shell at 97.6°
 Fifth shell: 172 satellites in a  shell at 97.6°

SpaceX previously had regulatory approval from the FCC to operate another 2,825 satellites in higher orbits between  and , in orbital planes inclined at 53.8°, 70.0°, 74.0° and 81.0°. 

On 17 April 2020, in documentation to the FCC, SpaceX requested a lower altitude of   and , which they noted will put the satellites closer to Starlink consumers and allow the network "to provide low-latency broadband to unserved and underserved Americans that is on par with service previously only available in urban areas". The modified plan submitted to the FCC foresees Ku-band and Ka-band satellites in the next phase of the Starlink network all operated at inclinations of 53.2°, 70.0° and 97.6°. The change will also improve service for U.S. government users in polar regions and allow for more rapid deployment of the network. The lower orbits will help ensure the satellites re-enter the atmosphere in a shorter time in case of failure and will enable them to broadcast signals at reduced power levels because they are closer to Earth, which SpaceX said will allow the fleet to be compliant with limits to reduce radio interference with other satellite and terrestrial wireless networks. The application covers 4,408 Starlink satellites, one fewer than envisioned under the previous architecture. SpaceX plans to launch another 7,500 V-band satellites into orbits around . The FCC approved the application in April 2021.

By June 2020, SpaceX had filed with Canadian regulatory authorities for a license to offer Starlink high-speed Internet services in Canada. This same month, SpaceX applied in the United States for use of the E-band in their Gen2 constellation, which is expected to include up to 30,000 satellites and provide complete global coverage.

By August 2020, a Falcon rocket was sent to SpaceX's Starlink Internet network with 58 more broadband relay nodes, to make the total of 653 satellites since May 2019. SpaceX is producing approximately 120 satellites a month.

In October 2020, SpaceX stated plans to deorbit all 60 prototype v0.9 satellites for "on-orbit debris mitigation". , 39 of 60 have reentered the Earth atmosphere. In October 2020, Canada granted a license to work there.

On 4 November 2020, SpaceX conducted its one millionth Starlink test and doubled the connection speed. Starlink beta testers have been reporting speeds over 150 megabits per second, above the range announced for the public beta test.

On 6 November 2020, Innovation, Science and Economic Development Canada announced regulatory approval for the Starlink low Earth orbit satellite constellation.

The Federal Communications Commission awarded SpaceX with nearly US$900 million worth of federal subsidies to support rural broadband customers through the company's Starlink satellite Internet network. SpaceX won subsidies to bring service to customers in 35 U.S. states. The Free Press advocacy group called the award to Starlink "another Hyperloop-style boondoggle", showing examples of territory awarded to Starlink in New York City, a strip mall near McCarran International Airport in Las Vegas, and other urban blocks that were labelled as underserved by the FCC. The National Rural Electric Cooperative Association also filed a complaint about the awards to Starlink.

SpaceX released a new group of 10 Starlink satellites on 24 January 2021, the first Starlink satellites in polar orbits. The launch also surpassed ISRO's record of launching the most of satellites in one mission (143), taking to 1,025 the cumulative number of satellites deployed for Starlink to that date.

In February 2021, SpaceX announced that Starlink has over 10,000 users, and opened up pre-orders to the public. Musk stated that the satellites are traveling on 25 orbital planes clustered between 53° north and south of the equator.

In February 2021, SpaceX completed raising an additional US$3.5 billion  in equity financing over the previous six months, to support the capital-intensive phase of the operational fielding of Starlink, plus the development of the Starship launch system. In April 2021, SpaceX clarified that they have already tested two generations of Starlink technology, with the second one having been less expensive than the first. The third generation, with laser intersatellite links, is expected to begin being launched "in the next few months [and will be] much less expensive than earlier versions".

In March 2021, SpaceX put an application into FCC for mobile variations of their terminal for vehicles, vessels and aircraft.

By May 2021, SpaceX announced that they had over 500,000 Starlink orders by consumers and almost 100,000 users in June 2021. and announced agreements with Google Cloud Platform and Microsoft Azure to provide on-ground compute and networking services for Starlink. Viasat made a legal attempt to temporarily halt Starlink launches. 

In June 2021, SpaceX applied to the FCC to use mobile Starlink transceivers on launch vehicles flying to Earth orbit, after having previously tested high-altitude low-velocity mobile use on a rocket prototype in May 2021.

By 1 October 2021, SpaceX had sold 5000 Starlink preorders in India, and announced that Sanjay Bhargava, who had worked with Elon Musk as part of a team that founded electronic payment firm, PayPal, would head the tech billionaire entrepreneur's Starlink satellite broadband venture in India.
Three months later, Bhargava resigned effective 31 December 2021 "for personal reasons" following the Indian government ordering SpaceX to halt selling preorders for Starlink service until SpaceX gains regulatory approval for providing satellite internet services in the country.

In February 2022, SpaceX announced Starlink Premium, a higher performance edition of the service. It provides a larger high-performance antenna and listed speeds of between 150 and 500Mbps, with a cost of $2500 for the antenna and a $500 monthly service fee. Users will also benefit from 24/7, prioritized support. Deliveries are advertised to begin in the second quarter of 2022.

On 3 February 2022, 49 satellites were launched as Starlink Group 4-7. Due to a significant increase in atmospheric drag caused by a G2-rated geomagnetic storm on 4 February, up to 40 of those satellites were expected to be lost. By 12 February, 38 satellites had reentered the atmosphere while the remaining 11 continued to raise their orbits.

On 26 February 2022, Elon Musk announced that the Starlink satellites had become active over Ukraine after a request from the Ukrainian government to replace internet services destroyed during the 2022 Russian invasion of Ukraine.

Launches 

Between February 2018 and 2022, SpaceX successfully launched 2,091 satellites into orbit.  In March 2020, SpaceX reported producing six satellites per day.

The deployment of the first 1,440 satellites was planned in 72 orbital planes of 20 satellites each, with a requested lower minimum elevation angle of beams to improve reception: 25° rather than the 40° of the other two orbital shells. SpaceX launched the first 60 satellites of the constellation in May 2019 into a  orbit and expected up to six launches in 2019 at that time, with 720 satellites (12 × 60) for continuous coverage in 2020.

Starlink satellites are also planned to launch on Starship, an under-development rocket of SpaceX that will launch 400 satellites at a time.

Constellation design and status 

Contains all v0.9 and higher satellite generations. Tintin A and Tintin B as test satellites are not included.

Early designs had all phase 1 satellites in altitudes of around . SpaceX initially requested to lower the first 1584 satellites, and in April 2020 requested to lower all other higher satellite orbits to about . This modification was approved in April 2021.

Availability by country 
In order to offer satellite services over any nation-state, International Telecommunication Union (ITU) regulations and long-standing international treaties require that landing rights be granted by each country jurisdiction. As a result, even though the Starlink network has near-global reach at latitudes below approximately 60°, broadband services to rural and underserved areas can only be provided in approximately nineteen countries to date. SpaceX can also have business operation and economic considerations that may make a difference in which countries Starlink service is offered, in which order, and how soon. For example, SpaceX formally requested authorization for Canada only in June 2020, the Canadian regulatory authority approved it in November 2020, and SpaceX rolled out service two months later, in January 2021. As of February 2022, Starlink services were on offer in 29 countries, with applications pending regulatory approval in many more. Japan's major mobile provider, KDDI, announced a partnership with SpaceX to begin offering in 2022 expanded connectivity for its rural mobile customers via 1,200 remote mobile towers.

Services 
SpaceX intends to provide satellite internet connectivity to underserved areas of the planet, as well as provide competitively priced service in more urbanized areas. The company has stated that the positive cash flow from selling satellite internet services would be necessary to fund their Mars plans.. Furthermore, SpaceX has long-term plans to develop and deploy a version of the satellite communication system to serve Mars.

In October 2020, SpaceX launched a paid-for beta service in the U.S. called "Better Than Nothing Beta", charging US$499 for a user terminal, with an expected service of "50 Mbps to 150 Mbps and latency from 20 ms to 40 ms over the next several months". From January 2021, the paid-for beta service was extended to other countries, starting with the United Kingdom.

The initial version of Starlink was limited to working within a few miles of the customers' registered address. In April 2021, Musk tweeted that users would be able to move the Starlink unit anywhere by the end of the year after more satellite launches and software updates. 

In February 2022, SpaceX announced Starlink Premium, a higher performance edition of the service. It provides a larger high-performance antenna and listed speeds of between 150 and 500Mbps, with a cost of $2500 for the antenna and a $500 monthly service fee.

Technology

Satellite hardware 
The Internet communication satellites were expected to be in the smallsat-class of -mass, and were intended to be in low Earth orbit (LEO) at an altitude of approximately , according to early public releases of information in 2015. In the event, the first large deployment of 60 satellites in May 2019 were  and SpaceX decided to place the satellites at a relatively low , due to concerns about the space environment. Initial plans  were for the constellation to be made up of approximately 4,000 cross-linked satellites, more than twice as many operational satellites as were in orbit in January 2015.

The satellites will employ optical inter-satellite links and phased array beam-forming and digital processing technologies in the Ku- and Ka-bands, according to documents filed with the U.S. Federal Communications Commission (FCC). While specifics of the phased array technologies have been disclosed as part of the frequency application, SpaceX enforced confidentiality regarding details of the optical inter-satellite links. Early satellites were launched without laser links. The inter-satellite laser links were successfully tested in late 2020.

The satellites will be mass-produced, at a much lower cost per unit of capability than previously existing satellites. Musk said, "We're going to try and do for satellites what we've done for rockets." "In order to revolutionize space, we have to address both satellites and rockets." "Smaller satellites are crucial to lowering the cost of space-based Internet and communications".

In February 2015, SpaceX asked the FCC to consider future innovative uses of the Ka-band spectrum before the FCC commits to 5G communications regulations that would create barriers to entry, since SpaceX is a new entrant to the satellite communications market. The SpaceX non-geostationary orbit communications satellite constellation will operate in the high-frequency bands above 24 GHz, "where steerable Earth station transmit antennas would have a wider geographic impact, and significantly lower satellite altitudes magnify the impact of aggregate interference from terrestrial transmissions".

Internet traffic via a geostationary satellite has a minimum theoretical round-trip latency of at least 477 milliseconds (ms; between user and ground gateway), but in practice, current satellites have latencies of 600 ms or more. Starlink satellites are orbiting at  to  of the height of geostationary orbits, and thus offer more practical Earth-to-sat latencies of around 25 to 35 ms, comparable to existing cable and fiber networks. The system will use a peer-to-peer protocol claimed to be "simpler than IPv6", it will also incorporate end-to-end encryption natively.

Starlink satellites use Hall-effect thrusters with krypton gas as the reaction mass for orbit raising and station keeping. Krypton Hall thrusters tend to exhibit significantly higher erosion of the flow channel compared to a similar electric propulsion system operated with xenon, but krypton is much more abundant and has a lower market price.

User terminals 

The system does not directly connect from its satellites to handsets (like the constellations from Iridium, Globalstar, Thuraya and Inmarsat). Instead, it is linked to flat user terminals the size of a pizza box, which will have phased array antennas and track the satellites. The terminals can be mounted anywhere, as long as they can see the sky. This includes fast-moving objects like trains. Photographs of the customer antennas were first seen on the internet in June 2020, supporting earlier statements by SpaceX CEO Musk that the terminals would look like a "UFO on a stick. Starlink Terminal has motors to self-adjust optimal angle to view sky". The antenna is known internally as "Dishy McFlatface".

In October 2020, SpaceX launched a paid-for beta service in the U.S. called "Better Than Nothing Beta", charging US$499 for a user terminal, with an expected service of "50 Mbps to 150 Mbps and latency from 20 ms to 40 ms over the next several months". From January 2021, the paid-for beta service was extended to other continents, starting with the United Kingdom.

SpaceX has announced Starlink Premium, a higher performance edition of the service. It provides a larger high-performance antenna and listed speeds of between 150 and 500Mbps, with a cost of $2500 for the antenna and a $500 monthly service fee.

In September 2020, SpaceX applied for permission to put terminals on 10 of its ships with the expectation of entering the maritime market in the future.

Ground stations 
SpaceX has made applications to the FCC for at least 32 ground stations in United States, and  has approvals for five of them (in five states).  Starlink uses the Ka-band to connect with ground stations.  

According to their filing, SpaceX's ground stations would also be installed on-site at Google data-centers world-wide.

Satellite revisions

MicroSat 
MicroSat-1a and MicroSat-1b were originally slated to be launched into  circular orbits at approximately 86.4° inclination, and to include panchromatic video imager cameras to film images of Earth and the satellite. The two satellites, "MicroSat-1a" and "MicroSat-1b" were meant to be launched together as secondary payloads on one of the Iridium-NEXT flights, but they were instead used for ground-based tests.

Tintin 
At the time of the June 2015 announcement, SpaceX had stated plans to launch the first two demonstration satellites in 2016, but the target date was subsequently moved out to 2018. SpaceX began flight testing their satellite technologies in 2018 with the launch of two test satellites. The two identical satellites were called MicroSat-2a and MicroSat-2b during development but were renamed Tintin A and Tintin B upon orbital deployment on 22 February 2018. The satellites were launched by a Falcon 9 rocket, and they were piggy-pack payloads launching with the Paz satellite.

Tintin A and B were inserted into a  orbit. Per FCC filings, they were intended to raise themselves to an  orbit, the operational altitude for Starlink LEO satellites per the earliest regulatory filings, but stayed close to their original orbits. SpaceX announced in November 2018 that they would like to operate an initial shell of about 1600 satellites in the constellation at about  orbital altitude, at an altitude similar to the orbits Tintin A and B stayed in.

The satellites orbit in a circular low Earth orbit at about  altitude in a high-inclination orbit for a planned six to twelve-month duration. The satellites communicate with three testing ground stations in Washington State and California for short-term experiments of less than ten minutes duration, roughly daily.

V0.9 (test) 
The 60 Starlink v0.9 satellites, launched in May 2019, have the following characteristics:
 Flat-panel design with multiple high-throughput antennas and a single solar array
 Mass: 
 Hall-effect thrusters using krypton as the reaction mass, for position adjustment on orbit, altitude maintenance and deorbit
 Star tracker navigation system for precision pointing
 Able to use Department of Defense-provided debris data to autonomously avoid collision
 Altitude of 
 95% of "all components of this design will quickly burn in Earth's atmosphere at the end of each satellite's lifecycle".

V1.0 (operational) 
The Starlink v1.0 satellites, launched since November 2019, have the following additional characteristics:
 100% of "all components of this design will quickly burn in Earth's atmosphere at the end of each satellite's lifecycle."
 Ka-band added
 Mass: 
 One of them, numbered 1130 and called DarkSat, had its albedo reduced using a special coating but the method was abandoned due to thermal issues and IR reflectivity.
 All satellite launched since the ninth launch at August 2020 have visors to block sunlight from reflecting from parts of the satellite to reduce its albedo further.

V1.5 (operational) 
 First batch of ten satellites launched into a 97.5° polar orbit on 24 January 2021 with lasers for inter-satellite communication.

 Mass: ~

 A further 338 laser-equipped satellites will launch into polar orbit from Vandenberg. SpaceX launched 51 of these laser-equipped satellites on 14 September 2021.

V2.0 (planned) 
 SpaceX was preparing for the production of Starlink v2.0 satellites in 2021. Starlink v2.0 satellites will be "significantly more capable" than v1.5 and begin launching in 2022.

Military capabilities

Military satellites 
In March 2018, the Space Development Agency (SDA) was formed by Under Secretary of Defense Michael D. Griffin (who was also a key participant in the founding of SpaceX).  He noted the new organization had "the sole mission to accelerate the development and fielding of new military space capabilities" with a focus on commercial low-cost Low Earth orbit satellites.

In October 2020, the Space Development Agency awarded SpaceX an initial US$150 million dual-use contract to develop a deluxe military version of the Starlink satellite bus. The first tranche of satellites are scheduled to launch September 2022 to form part of the Tracking Layer of the Space Force's National Defense Space Architecture (NDSA).

The NDSA will be composed of seven layers and mirrors concepts from the former Brilliant Pebbles system. Cost overruns had led to cancellation of these earlier programs but SpaceX and other reusable launch systems have mitigated concerns according to a 2019 Congressional Budget Office analysis. The new constellation also leverages Starlink and other commercial technology development to reduce costs, such as free-space optical laser terminals in a mesh network for secure command and control.

While much of the program is classified, it broadly envisions layers of LEO satellites, some containing space-based interceptors to track and neutralize perceived threats such as ballistic missiles.  Captain Joshua Daviscourt, USAF indicated the satellite constellations could include hypersonic re-entry vehicles or micro-missiles fielding pods of 100 interceptors onboard each satellite. Previous National Research Council studies show space-based interceptors could kinetically impact a target within 2 minutes of initiating a de-orbit. The Union of Concerned Scientists however warns that these weapon systems staged around the Earth would escalate tensions with Russia and China and called the project "fundamentally destabilizing".

Starlink's military satellite development is overseen internally at SpaceX by retired four-star general Terrence J. O'Shaughnessy.

Military user tests 
In 2019, tests by the United States Air Force Research Laboratory (AFRL) demonstrated a 610 Mbit/s data link through Starlink to a Beechcraft C-12 Huron aircraft in flight. Additionally, in late 2019, the United States Air Force successfully tested a connection with Starlink on an AC-130 Gunship.

In 2020, United States Air Force utilized Starlink in support of its Advanced Battlefield management system during a live-fire exercise. They demonstrated Starlink connected to a "variety of air and terrestrial assets" including the Boeing KC-135 Stratotanker.

Competition and market effects 

In addition to the OneWeb constellation, announced nearly concurrently with the SpaceX constellation, a 2015 proposal from Samsung outlined a 4,600-satellite constellation orbiting at  that could provide a zettabyte per month capacity worldwide, an equivalent of 200 gigabytes per month for 5 billion users of Internet data, but by 2020, no more public information had been released about the Samsung constellation. Telesat announced a smaller 117 satellite constellation in 2015 with plans to deliver initial service in 2021. Amazon announced a large broadband internet satellite constellation in April 2019, planning to launch 3,236 satellites in the next decade in what the company calls "Project Kuiper", a satellite constellation that will work in concert with Amazon's previously announced large network of twelve satellite ground station facilities (the "AWS ground station unit") announced in November 2018.

In February 2015, financial analysts questioned established geosynchronous orbit communications satellite fleet operators as to how they intended to respond to the competitive threat of SpaceX and OneWeb LEO communication satellites. In October 2015, SpaceX President Gwynne Shotwell indicated that while development continues, the business case for the long-term rollout of an operational satellite network was still in an early phase. 

By October 2017, the expectation for large increases in satellite network capacity from emerging lower-altitude broadband constellations caused market players to cancel some planned investments in new geosynchronous orbit broadband communications satellites.

Criticism and resistance

Light pollution 

The planned large number of satellites has been met with criticism from the astronomical community because of concerns over light pollution. Astronomers claim that the number of visible satellites will outnumber visible stars and that their brightness in both optical and radio wavelengths will severely impact scientific observations. While astronomers can schedule observations to avoid pointing where satellites currently orbit, it is "getting more difficult" as more satellites come online. The International Astronomical Union (IAU), National Radio Astronomy Observatory (NRAO), and Square Kilometre Array Organization (SKAO) have released official statements expressing concern on the matter.

On 20 November 2019, the four-meter Blanco telescope of the Cerro Tololo Inter-American Observatory (CTIO) recorded strong signal loss and the appearance of 19 white lines on a DECam shot (left image). This image noise was correlated to the transit of a Starlink satellite train, launched a week earlier.

SpaceX representatives and Musk have claimed that the satellites will have minimal impact, being easily mitigated by pixel masking and image stacking. However, professional astronomers have disputed these claims based on initial observation of the Starlink v0.9 satellites on the first launch, shortly after their deployment from the launch vehicle. In later statements on Twitter, Musk stated that SpaceX will work on reducing the albedo of the satellites and will provide on-demand orientation adjustments for astronomical experiments, if necessary. However, , only one Starlink satellite (Starlink 1130 / DarkSat) has experimental coating to reduce its albedo. The reduction in g-band magnitude is 0.8 magnitude (55%). Despite these measures, astronomers found that the satellites were still too bright thus making DarkSat essentially a "dead end".

On 17 April 2020, SpaceX wrote in a Federal Communications Commission (FCC) filing that it would test new methods of mitigating light pollution, and also provide access to satellite tracking data for astronomers to "better coordinate their observations with our satellites". On 27 April 2020, Musk announced that the company would introduce a new sunshade designed to reduce the brightness of Starlink satellites. , over 200 Starlink satellites have a sunshade. An October 2020 analysis found them to be only marginally fainter than DarkSat. A January 2021 study pinned the brightness at 31% of the original design.

According to a May 2021 study, "The large number of fast-moving transmitting stations (i.e. satellites) will cause further interference. New analysis methods could mitigate some of these effects, but data loss is inevitable, increasing the time needed for each study and limiting the overall amount of science done".

In February 2022, the International Astronomical Union (IAU) established a center to help astronomers deal with the adverse effects of satellite constellations such as Starlink. Work will include the development of software tools for astronomers, advancement of national and international policies, community outreach and work with industry on relevant technologies.

Space debris 
The large number of satellites employed by Starlink is claimed by critics to create long-term danger of space debris resulting from placing thousands of satellites in orbit and the risk of causing a satellite collision, potentially triggering a phenomenon known as Kessler syndrome. SpaceX has said that most of the satellites are launched at a lower altitude, and failed satellites are expected to deorbit within five years without propulsion. 

Early in the program, a near-miss occurred when SpaceX did not move a satellite that had a 1 in 1,000 chance of colliding with a European one, ten times higher than ESA's threshold for avoidance maneuvers. SpaceX subsequently fixed an issue with its paging system that had disrupted emails between ESA and SpaceX. ESA said it plans to invest in technologies to automate satellite collision avoidance maneuvers. In 2021, Chinese authorities lodged a complaint with the United Nations, saying their space station had performed evasive maneuvers that year to avoid Starlink satellites. In the document, Chinese delegates said that the continuously maneuvering Starlink satellites posed a risk of collision, and two close encounters with the satellites in July and October constituted dangers to the life or health of astronauts aboard the Chinese Tiangong space station.

On 3 February 2022, a launch of 49 new Starlink satellites encountered a geomagnetic storm. The storm caused the atmosphere to warm and density at the low deployment altitudes to increase. Due to the increased drag, up to 40 of the satellites will reenter or already have reentered the Earth’s atmosphere within the week according to SpaceX.

United States federal funding 
SpaceX was challenged regarding Starlink in February 2021 when the National Rural Electric Cooperative Association (NRECA) pressured the U.S. Federal Communications Commission (FCC) to "actively, and aggressively, and thoughtfully vet" the subsidy applications of SpaceX and other broadband providers. SpaceX has provisionally won US$886 million for a commitment to provide service to 642,925 locations in 35 states as part of the Rural Digital Opportunity Fund (RDOF).

The NRECA criticized the funding allocation because Starlink will include service to locations — such as Harlem and terminals at Newark Liberty International Airport and Miami International Airport — that are not rural, and because SpaceX will build the infrastructure and serve any customers who request service with or without the FCC subsidy. Additionally, Jim Matheson, chief executive officer of the NRECA voiced his concern about technologies that have not been proven to meet the high speeds required for the award category. Starlink was specifically criticized for being still in beta testing and an unproven technology.

Customer service 
Customers have criticized Starlink for its customer service. For example, a customer complained that it was "non-existent" after they waited 10 months for their Internet access.

Similar or competitive systems 

 OneWeb satellite constellation — a satellite constellation project that began operational deployment of satellites in 2020.

 China national satellite internet project — a planned satellite internet offering for the Chinese market.

 Kuiper Systems – a planned 3,236 LEO satellite Internet constellation by an Amazon subsidiary.

 Hughes Network Systems — a current broadband satellite provider providing fixed, cellular backhaul, and airborne antennas.

 Viasat, Inc. — a current broadband satellite provider providing fixed, ground mobile, and airborne antennas.

 O3b – Medium Earth orbit constellation that provides access to mobile phone operators and internet service providers. It covers only the equatorial region.

See also 

 Orbcomm – an operational constellation used to provide global asset monitoring and messaging services from its constellation of 29 LEO communications satellites orbiting at 775 km
 Globalstar – an operational low Earth orbit (LEO) satellite constellation for satellite phone and low-speed data communications
 Iridium satellite constellation — an operational constellation of 66 active satellites used to provide global satellite phone service
 Lynk Global – a satellite-to-mobile-phone satellite constellation with the objective to coverage to traditional low-cost mobile devices
 Teledesic – a former (1990s) venture to accomplish broadband satellite internet services
 Project Loon – former concept to provide internet access via balloons in the stratosphere

Notes

References

External links 

 FCC FORM 442 – FEDERAL COMMUNICATIONS COMMISSION APPLICATION FOR NEW OR MODIFIED RADIO STATION UNDER PART 5 OF FCC RULES – EXPERIMENTAL RADIO SERVICE, SpaceX, 29 May 2015 application for communications spectrum allocation for technology development and testing flights beginning as early as 2015.
 Official Starlink Website
 Starlink Satellite Locations
 See A Satellite Tonight shows when Starlink satellites can be seen.
 Shows real-time Starlink satellites position
 Starlink Professional Installers Directory

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Communications satellites in low Earth orbit
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