cosmos.wikisort.org - Spacecraft

Starlink is a satellite internet constellation operated by SpaceX,[3] providing satellite Internet access coverage to 40 countries. It also aims for global mobile phone service after 2023.[4] SpaceX started launching Starlink satellites in 2019. As of September 2022, Starlink consists of over 3,000 mass-produced small satellites in low Earth orbit (LEO),[5] which communicate with designated ground transceivers. In total, nearly 12,000 satellites are planned to be deployed, with a possible later extension to 42,000. Starlink provides internet access to over 500,000 subscribers as of June 2022.[6]

Starlink

60 Starlink satellites stacked together before deployment on 24 May 2019
Manufacturer	SpaceX
Country of origin	United States
Operator	SpaceX
Applications	Internet service
Website	starlink.com
Specifications
Spacecraft type	Small satellite
Launch mass	v 0.9: 227 kg (500 lb) v 1.0: 260 kg (570 lb) v 1.5: ~295 kg (650 lb)[1] v 2.0: ~1,250 kg (2,760 lb)[2]
Equipment	Ku-, Ka-, and E-band phased array antennas Laser transponders (some units) Hall-effect thrusters
Regime	Low Earth orbit Sun-synchronous orbit
Production
Status	Active

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.[7] SpaceX expects more than $30 billion in revenue by 2025 from its satellite constellation, while revenues from its launch business were expected to reach $5 billion in the same year.[8][9]

Astronomers have raised concerns about the constellations' effect on ground-based astronomy and how the satellites will add to an already congested orbital environment.[10][11] SpaceX has attempted to mitigate astronomy concerns by implementing several upgrades to Starlink satellites aimed at reducing their brightness during operation.[12] 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.[13]

History

Background

Constellations of low Earth orbit satellites were first conceptualized in the mid-1980s as part of the Strategic Defense Initiative, where weapons were to be staged in orbit to intercept ballistic missiles on short notice. The potential for low-latency communication was also recognized and development offshoots in the 1990s led to numerous commercial megaconstellations using around 100 satellites 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.[14][15]

In June 2004, the newly formed company SpaceX acquired a stake in Surrey Satellite Technology (SSTL) as part of a “shared strategic vision”.[16] SSTL was at that time working to extend the Internet into space.[17] However, SpaceX's stake was eventually sold back to EADS Astrium in 2008 after the company became more focused on navigation and Earth observation.[18]

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.[19] However, these discussions broke down by June 2014, and SpaceX instead filed an ITU application via the Norway telecom regulator under the name STEAM.[20] SpaceX confirmed the connection in the 2016 application to license Starlink with the FCC.[21] SpaceX trademarked the name Starlink for their satellite broadband network;[22] the name was inspired by the book The Fault in Our Stars.[23]

Development phase (2015–2020)

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.[24][25] 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.[26][27]

Starting with 60 engineers, the company operated in 2,800 m² (30,000 sq ft) of leased space, and by January 2017 had taken on a 2,800 m² (30,000 sq ft) second facility, both in Redmond.[28] 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.[29] In July 2016, SpaceX acquired an additional 740 m² (8,000 sq ft) creative space in Irvine, California (Orange County).[30] The Irvine office would include signal processing, RFIC, and ASIC development for the satellite program.[31]

By October 2016, the satellite division was focusing on a significant business challenge of achieving a sufficiently low-cost design for the user equipment. 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".[32]

In November 2016, SpaceX filed an application with the FCC for a "non-geostationary orbit (NGSO) satellite system in the Fixed-Satellite Service using the Ku- and Ka- frequency bands".[33] 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",[34] it would comprise 7,518 satellites and would orbit at just 340 km (210 mi) altitude,[35] while the smaller, originally planned group of 4,425 satellites would operate in the K_a- and K_u-bands and orbit at 1,200 km (750 mi) altitude.[34][35]

In September 2017, the FCC ruled that half of the constellation must be in orbit within six years to comply with licensing terms, while the full system should be in orbit within nine years from the date of the license.[36]

SpaceX filed documents in late 2017 with the 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."[37]

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).[38][39] 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.[40]

In May 2018, SpaceX expected the total cost of development and buildout of the constellation to approach $10 billion.[7] In mid-2018, SpaceX reorganized the satellite development division in Redmond, and terminated several members of senior management.[29]

In November 2018, SpaceX received U.S. regulatory approval to deploy 7,518 broadband satellites, in addition to the 4,425 approved earlier.[41][42] SpaceX also made new regulatory filings with the U.S. 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 1,150 km (710 mi) in a "new lower shell of the constellation" at only 550 km (340 mi)[43] orbital altitude.[44][45] These satellites would effectively operate in a third orbital shell, a 550 km (340 mi) orbit, while the higher and lower orbits at approximately 1,200 km (750 mi) and approximately 340 km (210 mi) 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 550 km (340 mi) – altitude shell, and subsequently placing approximately 2,800 Ku- and Ka-band spectrum satellites at 1,150 km (710 mi) and approximately 7,500 V-band satellites at 340 km (210 mi).[46] In total, nearly 12,000 satellites were planned to be deployed, with (as of 2019) a possible later extension to 42,000.[47]

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.[48]

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[49][50] – and aircraft-borne antenna operation from four distributed United States airfields; as well as five ground-to-ground test locations.[51][52]

By late 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.[53] 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".[46]

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.[54] That month, 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.[55]

In November 2020, Starlink beta internet service was opened to the public.[56] Starlink beta testers reported speeds over 150 megabits per second, above the range announced for the public beta test.[57]

Commercial service (2021–)

In February 2021, SpaceX opened up pre-orders to the public.[58] SpaceX completed raising an additional $3.5 billion in equity financing over the previous six months,[59][60] to support the capital-intensive phase of the operational fielding of Starlink, plus the development of the Starship launch system.[59] 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 inter-satellite links, is expected to begin launching "in the next few months [and will be] much less expensive than earlier versions".[59]

As of September 2022^[update], SpaceX has over 2,300 functioning Starlink satellites in orbit,[61] and over 500,000 active subscribers.[62] They continue to launch up to 53 more satellites per Falcon 9 flight.

Month	Approx. number of subscribers
February 2021	10,000 [63]
June 2021	100,000 [64]
February 2022	250,000
May 2022	400,000
June 2022	500,000 [62]
September 2022	700,000 [65]

On 6 November 2020, Innovation, Science and Economic Development Canada announced regulatory approval for the Starlink low Earth orbit satellite constellation.[66]

The FCC initially awarded SpaceX with $885.5 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.[67] The $885.5 million aid package was revoked in August 2022, with the FCC stating that Starlink "failed to demonstrate" its ability to deliver the promised service.[68] SpaceX later appealed the decision saying they met or surpassed all RDOF deployment requirements that existed during bidding and that the FCC created "new standards that no bidder could meet today".[69]

In March 2021, SpaceX put an application into FCC for mobile variations of their terminal for vehicles, vessels and aircraft.[70][71]

In May 2021, SpaceX announced agreements with Google Cloud Platform and Microsoft Azure to provide on-ground compute and networking services for Starlink.[72] Viasat made a legal attempt to temporarily halt Starlink launches.[73] 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.[74]

By 1 October 2021, SpaceX had sold 5000 Starlink preorders in India,[75] 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.[76] Three months later, Bhargava resigned "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.[75]

In 2022 SpaceX announced the Starlink Business service tier.[77] The FCC also approved the licensing of Starlink services to boats, aircraft, and moving vehicles.[78]

In May 2022, Starlink entered the Philippine market, and is the company's first Asian deployment, due to a landmark legislative change (RA 11659, Public Services Act) about all-foreign allowance of company ownership in regards to utility entities such as internet and telco companies. Starlink was able to obtain a provisional permission from the country's Department of Information and Communication Technologies (DICT), National Telecommunications Commission (NTC) and Department of Trade and Industry (DTI) and will soon start commercial services, aimed at regions with lower internet connectivity.[79]

In May 2022, Chinese military researchers published an article in a peer-reviewed journal describing a strategy for destroying the Starlink constellation if they threaten national security.[80][81][82] The researchers specifically highlight concerns with reported Starlink military capabilities. Elon later announced "Starlink is meant for peaceful use / to mend the fault in our stars",[83] a quote mirroring Ronald Reagan's 1983 proposal for the "Star Wars" program to bring peace by rendering nuclear weapons impotent and obsolete.[84] The head of Russia's space agency, Dmitry Rogozin, had earlier warned Musk that "you will have to answer in an adult way, Elon, no matter how you play the fool."[85]

In August 2022, SpaceX secured its first contract for services in the passenger shipping industry. Royal Caribbean Group has added Starlink internet to Freedom of the Seas and plans to offer the service on 50 ships under its Royal Caribbean International, Celebrity Cruises, and Silversea Cruises brands by March 2023.[78] Starlink services on private jet charter flights in the US by JSX are expected to begin in late 2022, and Hawaiian Airlines has contracted to provide "Starlink services on transpacific flights to and from Hawaii in 2023."[78]

According to Ookla, between Q1 and Q2 2022, Starlink speeds decreased worldwide as more people signed up for Starlink, although SpaceX has said that Starlink speeds will improve once more satellites are operational.[86]

Services

Satellite internet

Starlink provides satellite internet connectivity to underserved areas of the planet, as well as 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.[87] Furthermore, SpaceX has long-term plans to develop and deploy a version of the satellite communication system to serve Mars.[88]

In October 2020, SpaceX launched a paid-for beta service in the U.S. called "Better Than Nothing Beta", charging $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".[89] From January 2021, the paid-for beta service was extended to other countries, starting with the United Kingdom.[90]

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.[91]

In February 2022, SpaceX announced Starlink Business, a higher performance edition of the service. It provides a larger high-performance antenna and listed speeds of between 150 and 500Mbit/s, with a cost of $2500 for the antenna and a $500 monthly service fee.[77] The service includes 24/7, prioritized support.[77] Deliveries are advertised to begin in the second quarter of 2022.[92]

On 23 May 2022, SpaceX rolled out Starlink For RVs, a new edition of the service that lets customers pay more to skip waitlists to connect to its broadband satellites without a fixed address, although connection speeds for other users will be prioritized.[93]

On 7 July 2022 SpaceX announced Starlink Maritime, a new addition to help support users, and companies, on the ocean. Only working on the water, unable to work on land, the advertised speed for the service is set up to 350 Mbps. However it comes at the one time price of $10,000 for the two user terminals, and $5,000 monthly price.[94][95]

In September 2022, SpaceX sent out an email to users with pre-orders about a service called Best Effort. It allows those still waiting in a full capacity cell to receive the unused bandwidth of their cell, while still being on the waiting list for more prioritized service. The price and equipment are the same as the residential service coming in at $110 per month.[96][97]

Satellite cellular service

In August 2022, T-Mobile US and SpaceX announced a partnership to add satellite cellular service to Starlink Gen2 satellites, and provide dead-zone cell phone coverage across the US using existing midband PCS spectrum that T-Mobile owns.[98][99] Cell coverage will begin with messaging and expand to include voice and limited data services later, with testing to begin in 2023. With Starlink Gen2 sats in low-Earth orbit using existing PCS spectrum, T-Mobile plans to be able to connect by satellite to ordinary mobile devices, unlike previous generations of satellite phones which used specialized Earth-bound radios to connect to geosynchronous satellites with characteristic long communications lag time.[4] T-Mobile has offered to extend the offering globally if cellular carriers in other countries wish to exchange roaming services via the T-Mobile partnership with SpaceX, with other carriers responsible for working with their regulators to enable midband data communication landing rights on a country-by-country basis. Bandwidth will be limited to approximately 2 to 4 megabits per second spread across a very large cell coverage area; so limited to approximately 1000 to 2000 voice calls, or millions of text messages, across an entire cell. The size of a single coverage cell has not yet been publicly released, but the satellites are 7 meters long, and the antenna would fold out to be "roughly 25 square meters".[98]

Military satellites

In March 2018, the Space Development Agency (SDA) was formed by Under Secretary of Defense Michael D. Griffin as part of a Trump Administration initiative to resurrect the Strategic Defense Initiative (SDI).[100] The new organization intends to accelerate the development of new military space capabilities with a focus on industry-procured low-cost Low Earth orbit satellite platforms.[101]

In October 2020, the Space Development Agency awarded SpaceX an initial $150 million dual-use contract to develop a deluxe military version of the Starlink satellite bus.[102] The first tranche of satellites were originally scheduled to launch September 2022 to form part of the Tracking Layer of the Space Force's National Defense Space Architecture (NDSA).[103] However the launch schedule slipped to mid-December 2022 after supply-chain difficulties arose procuring "radio microelectronics".[104]

The NDSA will be composed of seven layers with specific functions: data transport, battle management, missile tracking, custody/weapons targeting, navigation/PNT, deterrence, and ground support.[105][106] Historically, space-based missile defense concepts (e.g., Brilliant Pebbles) were expensive, but reusable launch systems have mitigated costs according to a 2019 Congressional Budget Office analysis.[107] NSDA leverages existing commercial satellite bus development such as Starlink to reduce costs, including free-space optical laser terminals for a secure command and control mesh network.[108] The 2019 Missile Defense Review notes space-based sensing enables "improved tracking and potentially targeting of advanced threats, including HGVs and hypersonic cruise missiles".[109] " However, the Union of Concerned Scientists warns developments could escalate tensions with Russia and China and called the project "fundamentally destabilizing".[110]

Starlink's military satellite development is overseen internally at SpaceX by retired four-star general Terrence J. O'Shaughnessy.[111]^{[failed verification]}

Military communications

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.[112] Additionally, in late 2019, the United States Air Force successfully tested a connection with Starlink on an AC-130 Gunship.[113]

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.[114]

Use in Ukraine

On 26 February 2022, Elon Musk announced that the Starlink satellites had become active over Ukraine after a request from the Ukrainian government[115] to replace internet services destroyed during the 2022 Russian invasion of Ukraine.[116] By 6 April 2022, SpaceX had sent over 5000 Starlink terminals to Ukraine to allow Ukrainians access to the Starlink network;[117] SpaceX had donated 73% or 3,667 and removed the monthly service fees, and USAID had purchased the balance of the terminals.[118] According to The Washington Post, The Starlink equipment sent to Ukraine was funded by SpaceX including partial funding by the U.S. Agency for International Development, as well as the governments of France and Poland.[119][120] By mid August, Ukraine internet service was being provided by more than 20,000 Starlink terminals, some from foreign partners and volunteers, in addition to many provided directly by SpaceX. During the war, Ukrainians can use Starlink terminals without paying the normal monthly subscription fee.[121]

In May 2022 a Starlink-enabled Ukrainian Internet App was the key component of a successful new artillery fire coordination system.[122] While military and government use of the Starlink has been the most important aspect of opening Ukraine to low-altitude satellite internet services in early 2022, civilians are also heavily using the technology "to keep in touch with the outside world and tell loved ones that they are alive."[121]

Availability and regulatory approval by country

In order to offer satellite services in any nation-state, International Telecommunication Union (ITU) regulations and long-standing international treaties require that landing rights be granted by each country jurisdiction, and within a country, by the national communications regulators. As a result, even though the Starlink network has near-global reach at latitudes below approximately 60°, broadband services can only be provided in 40 countries as of September 2022.[123] 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,[124] the Canadian regulatory authority approved it in November 2020,[66] and SpaceX rolled out service two months later, in January 2021.[125] As of September 2022, Starlink services were on offer in 40 countries,[123] with applications pending regulatory approval in many more.[126]

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.[127]

On 25 April 2022, Hawaiian Airlines announced an agreement with Starlink to provide free internet access on its aircraft, becoming the first airline to use Starlink.[128] By July 2022, Starlink internet service was available in 36 countries and 41 markets.[129]

In May 2022, it was announced that regulatory approval had been granted for Nigeria, Mozambique, and the Philippines.[130][131][132]^{[clarification needed]}

Countries

#	Continent	Country	Debut	Notes
1	North America	United States  Puerto Rico  United States Virgin Islands	Limited trials August 2020,[133] public beta November 2020[56]	First authorized region, The FCC approved SpaceX's proposed modification of its license in 2021.[134]
2	North America	Canada	January 2021[125]
3	Europe	United Kingdom	January 2021[135]
4	Europe	Germany	March 2021[136]
5	Oceania	New Zealand	April 2021[137]
6	Oceania	Australia	April 2021[138]
7	Europe	France  Saint Martin  Saint Barthélemy  Guadeloupe  Martinique	Original debut May 2021,[139][140] Revoked April 2022,[141] Re-approved June 2022[142]	Approval originally given in February 2021 but the Conseil d'État annulled that Decision on 5 April 2022 due to lack of public consultation.[141] Approval was given again after consultation was completed on 2 June 2022.[142] Service expanded to Saint Martin and Saint Barthélemy in July 2022.[129] Service expanded to Martinique and Guadeloupe in September 2022.[143]
8	Europe	Austria	May 2021[139]
9	Europe	Netherlands	May 2021[144]
10	Europe	Belgium	May 2021[145]
11	Europe	Ireland	Limited trials April 2021,[146] public beta July 2021[147]
12	Europe	Denmark	July 2021[148]
13	Europe	Portugal	August 2021[149]
14	Europe	Switzerland	August 2021[150]
15	South America	Chile	Limited trials July 2021,[151] public beta September 2021[152]
16	Europe	Poland	September 2021[153]
17	Europe	Italy	September 2021[154]
18	Europe	Czech Republic	September 2021[155]
19	Europe	Sweden	October 2021[156]	Available in a small southern part of the country due to the limited satellite coverage.
20	North America	Mexico	November 2021[157]
21	Europe	Croatia	November 2021[158]
22	Europe	Lithuania	December 2021[159][160]
23	Europe	Spain	January 2022[161]
24	Europe	Slovakia	January 2022[162]
25	Europe	Slovenia	January 2022[163]
26	Oceania	Tonga	February 2022[164]	Emergency relief provided one month after the 2022 Hunga Tonga–Hunga Ha'apai eruption and tsunami, ground station established in neighboring Fiji for six months
27	South America	Brazil	January 2022[165][166]
28	Europe	Bulgaria	February 2022[167]
29	Europe	Ukraine	February 2022[115][168][116]	Initially supplied as emergency relief in response to the 2022 Russian invasion of Ukraine
30	Europe	Romania	April 2022[169]
31	Europe	Greece	April 2022[170]
32	Europe	Latvia	April 2022[171]
33	Europe	Hungary	May 2022[172]
34	Europe	North Macedonia	June 2022[173]
35	Europe	Luxembourg	July 2022[129]
36	North America	Dominican Republic	July 2022[174]
37	Europe	Moldova	August 2022[175]
38	Europe	Estonia	August 2022[176]
39	South America	Colombia	August 2022[177][178][179][180]
40	Europe	Norway	August 2022[181]
41	Europe	Malta	September 2022[123]
42	Asia	Iran	September 2022[182]	Activated in response to Iranian censorship as a result of Iranian protests against compulsory hijab.[183]
43	Asia	Japan	October 2022[184]

Technology

Satellite hardware

The Internet communication satellites were expected to be in the smallsat-class of 100 to 500 kg (220 to 1,100 lb)-mass, and were intended to be in low Earth orbit (LEO) at an altitude of approximately 1,100 km (680 mi), according to early public releases of information in 2015. In the event, the first large deployment of 60 satellites in May 2019 were 227 kg (500 lb)[185] and SpaceX decided to place the satellites at a relatively low 550 km (340 mi), due to concerns about the space environment.[186] Initial plans as of January 2015^[update] were for the constellation to be made up of approximately 4,000 cross-linked[187] satellites, more than twice as many operational satellites as were in orbit in January 2015.[27]

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. FCC.[188][189] 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.[190] Early satellites were launched without laser links. The inter-satellite laser links were successfully tested in late 2020.[191][192]

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."[193] "In order to revolutionize space, we have to address both satellites and rockets."[27] "Smaller satellites are crucial to lowering the cost of space-based Internet and communications".[194]

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".[195]

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 1⁄105 to 1⁄30 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.[196] The system will use a peer-to-peer protocol claimed to be "simpler than IPv6", it will also incorporate end-to-end encryption natively.[197]

Starlink satellites use Hall-effect thrusters with krypton gas as the reaction mass[185][198] for orbit raising and station keeping.[199] 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.[200]

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.[187] This includes fast-moving objects like trains.[201] 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".[202] The antenna is known internally as "Dishy McFlatface".[203][204]

In October 2020, SpaceX launched a paid-for beta service in the U.S. called "Better Than Nothing Beta", charging $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".[89] From January 2021, the paid-for beta service was extended to other continents, starting with the United Kingdom.[90]

A larger, high-performance version of the antenna is available for use with the Starlink Business service tier.[77]

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.[205]

Ground stations

SpaceX has made applications to the FCC for at least 32 ground stations in United States, and as of July 2020^[update] has approvals for five of them (in five states). Starlink uses the Ka-band to connect with ground stations.[206]

A typical ground station right now has nine 2.86m antennas in a 400 sqm fenced in area.[207]

According to their filing, SpaceX's ground stations would also be installed on-site at Google data-centers world-wide.[72]

Satellite revisions

MicroSat

MicroSat-1a and MicroSat-1b were originally slated to be launched into 625 km (388 mi) circular orbits at approximately 86.4° inclination, and to include panchromatic video imager cameras to film images of Earth and the satellite.[208] 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.[209]

Tintin

At the time of the June 2015 announcement, SpaceX had stated plans to launch the first two demonstration satellites in 2016,[210] but the target date was subsequently moved out to 2018.[211] SpaceX began flight testing their satellite technologies in 2018[211] with the launch of two test satellites. The two identical satellites were called MicroSat-2a and MicroSat-2b[212] 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 514 km (319 mi) orbit. Per FCC filings,[213] they were intended to raise themselves to an 1,125 km (699 mi) 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 550 km (340 mi) orbital altitude, at an altitude similar to the orbits Tintin A and B stayed in.[44]

The satellites orbit in a circular low Earth orbit at about 500 km (310 mi) altitude[214] 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.[210][215]

v0.9 (test)

The 60 Starlink v0.9 satellites, launched in May 2019, have the following characteristics:[185]

• Flat-panel design with multiple high-throughput antennas and a single solar array
• Mass: 227 kg (500 lb)
• 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[216]
• Altitude of 550 km (340 mi)
• 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:^{[citation needed]}

• 100% of all components of this design will completely demise, or burn up, in Earth's atmosphere at the end of each satellite's life.[217]
• K_a-band added[218]
• Mass: 260 kg (570 lb)
• 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.[219][220]
• All satellites 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.[221][222][223][224]

v1.5 (operational)

The Starlink v1.5 satellites, launched since 24 January 2021, have the following additional characteristics:

• Lasers for inter-satellite communication[225]
• Mass: ~295 kg (650 lb)
• Visors that blocked sunlight were removed from satellites launched from September 2021 onwards.[226]

v2.0 (planned)

SpaceX was preparing for the production of Starlink v2.0 satellites by early 2021.[227] Starlink v2.0 satellites will be "almost an order of magnitude more capable than v1.0" in terms of communications bandwidth.

SpaceX hopes to begin launching Starlink v2.0 in 2022. As of May 2022^[update], SpaceX said publicly that all Gen2 Starlink sats would need to be launched on Starship, as they are too large to fit inside a Falcon 9 fairing.[228] However, in August 2022, SpaceX made formal regulatory filings with the FCC that indicated they would build the Gen2 Starlinks in two different form factors: one with the components laid out in such a way that they could be launched in Falcon 9, and one laid out in the 7-meter long form factor that could only be launched on Starship. The smaller one is being planned as a backup, in the event that regular operational payload-delivery Starship launches do not occur as soon as SpaceX would like.[98][229]

Starlink v2.0 is both larger and heavier than Starlink v1 satellites:

• Lasers for inter-satellite communication[230]
• Mass: ~1,250 kg (2,760 lb)[231][229]
• Length: ~7 m (23 ft) (Starship form factor)[231][229]
  TBD, <7m (Falcon 9 form factor)[98][229]
• Further improvements to reduce its brightness, including the use of a dielectric mirror film.[232][233]
• Gen2 Starlink satellites will also include a very large antenna to communicate in the existing midband PCS spectrum, one that will allow cell phone network customers to be able to connect by satellite through their regular mobile devices.[98] This communication is supplemental to the existing K_u-band and K_a-band antennas, and intersatellite laser links, that have been on the first generation satellites launching as of mid-2022.

Launches

Between February 2018 and 2022, SpaceX successfully launched 2,091 satellites into orbit. In March 2020, SpaceX reported producing six satellites per day.[234]

The deployment of the first 1,440 satellites was planned in 72 orbital planes of 20 satellites each,[235] with a requested lower minimum elevation angle of beams to improve reception: 25° rather than the 40° of the other two orbital shells.[44]^: 17 SpaceX launched the first 60 satellites of the constellation in May 2019 into a 550 km (340 mi) orbit and expected up to six launches in 2019 at that time, with 720 satellites (12 × 60) for continuous coverage in 2020.[236][237]

Starlink satellites are also planned to launch on Starship, an under-development rocket of SpaceX with a much larger payload capability. The initial announcement included plans to launch 400 Starlink (version 1.0) satellites at a time.[238] Current plans now call for Starship to be the only launch vehicle to be used to launch fewer of the much larger Starlink version 2.0.

Constellation design and status

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

Phase	Group designation	Orbital shells		Orbital planes[239]			Completion date		Deployed satellites
		Altitude (km)	Planned satellites	Incli­nation	Count	Satellites per	Half	Full	Active, 10 October 2022	Decaying/ deorbited, 10 October 2022
1[240]	Group 1[241]	550 km (340 mi)	1584[242]	53.0°	72	22	1 August 2022[243]	March 2027 (planned)	1469[244]	256[244]
	Group 2	570 km (350 mi)	720	70°	36	20			50[244]	1[244]
	Group 3[245]	560 km (350 mi)	348	97.6°	6	58			187[244]	10[244]
	Group 4	540 km (340 mi)	1584	53.2°	72	22			1411[244]	65[244]
	Group 5[241]	560 km (350 mi)	172	97.6°	4	43			0
2[246]		335.9 km (208.7 mi)	2493	42.0°			November 2024 (planned)	November 2027 (planned)	0
		340.8 km (211.8 mi)	2478	48.0°					0
		345.6 km (214.7 mi)	2547	53.0°					0

Early designs had all phase 1 satellites in altitudes of around 1,100–1,300 km (680–810 mi). SpaceX initially requested to lower the first 1584 satellites, and in April 2020 requested to lower all other higher satellite orbits to about 550 km (340 mi).[247][248] In April 2020, SpaceX modified the architecture of the Starlink network. SpaceX submitted an application to the 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 550 km (340 mi) in planes inclined 53.0°,[235] with no change to the first shell of the constellation launched largely in 2020.[249] SpaceX also applied in the United States for use of the E-band in their constellation[250] The FCC approved the application in April 2021.[251][252][253]

• First shell: 1,440 in a 550 km (341.8 mi) altitude shell at 53.0° inclination
• Second shell: 1,440 in a 540 km (335.5 mi) shell at 53.2° inclination
• Third shell: 720 in a 570 km (354.2 mi) shell at 70° inclination
• Fourth shell: 336 in a 560 km (348.0 mi) shell at 97.6° inclination
• Fifth shell: 172 satellites in a 560 km (348.0 mi) shell at 97.6° inclination

SpaceX previously had regulatory approval from the FCC to operate another 2,825 satellites in higher orbits between 1,110 km (690 mi) and 1,325 km (823 mi), in orbital planes inclined at 53.8°, 70.0°, 74.0° and 81.0°.

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 satellites in one mission (143), taking to 1,025 the cumulative number of satellites deployed for Starlink to that date.[254][255]

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, predictions were that up to 40 of the 49 satellites might be lost.[256] In the event, 38 satellites reentered the atmosphere by 12 February while the remaining 11 were able to raise their orbits and avoid loss due to the storm.[257]

Impact on astronomy

The planned large number of satellites has been met with criticism from the astronomical community because of concerns over light pollution.[258][259][260] 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.[261] 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.[262][263][264]

On 20 November 2019, the four-meter (13') 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 (right image). This image noise was correlated to the transit of a Starlink satellite train, launched a week earlier.[265]

SpaceX representatives and Musk have claimed that the satellites will have minimal impact, being easily mitigated by pixel masking and image stacking.[266] 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.[267][268][269][270] 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.[271][272] One Starlink satellite (Starlink 1130 / DarkSat) launched with an experimental coating to reduce its albedo. The reduction in g-band magnitude is 0.8 magnitude (55%).[273][274] Despite these measures, astronomers found that the satellites were still too bright thus making DarkSat essentially a "dead end".[275]

On 17 April 2020, SpaceX wrote in an 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".[276][277] On 27 April 2020, Musk announced that the company would introduce a new sunshade designed to reduce the brightness of Starlink satellites.[276] As of 15 October 2020^[update], over 200 Starlink satellites had a sunshade. An October 2020 analysis found them to be only marginally fainter than DarkSat.[278] A January 2021 study pinned the brightness at 31% of the original design.[279]

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".[280]

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.[281]

In June 2022, the IAU released a website for astronomers to deal with some adverse effects via satellite tracking. This will enable astronomers to be able to track satellites to be able to avoid and time them for minimal impact on current work.[282]

Increased risk of satellite collision

The large number of satellites employed by Starlink may 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.[283][284] 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.[285]

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.[286][287] 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.[288] 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.[289]

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.[290]

All these reported issues, plus current plans for the extension of the constellation, motivated a formal letter from National Telecommunications and Information Administration (NTIA) on behalf of the National Aeronautics and Space Administration (NASA) and the National Science Foundation (NSF), submitted to FCC on 8 February 2022, warning about the potential impact on LEO orbit, increased collision risk, impact on science missions, rocket launches, International Space Station and Radio frequencies Interferences. Resting credibility on the arguments for collision self-avoidance reported by SpaceX. [291]

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 1,400 km (870 mi) that could provide a zettabyte per month capacity worldwide, an equivalent of 200 gigabytes per month for 5 billion users of Internet data,[292][293] 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.[294] 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[295] with Amazon's previously announced large network of twelve satellite ground station facilities (the "AWS ground station unit") announced in November 2018.[296]

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.[297] 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.[298]

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.[299]

SpaceX was challenged regarding Starlink in February 2021 when the National Rural Electric Cooperative Association (NRECA), a political interest group representing traditional rural internet service providers, urged the U.S. Federal Communications Commission (FCC) to "actively, and aggressively, and thoughtfully vet" the subsidy applications of SpaceX and other broadband providers. At the time, SpaceX had provisionally won $886 million for a commitment to provide service to approximately 643,000 locations in 35 states as part of the Rural Digital Opportunity Fund (RDOF).[300] The NRECA criticisms included that the funding allocation to Starlink would 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 was planning to build the infrastructure and serve any customers who request service with or without the FCC subsidy.[300] Additionally, Jim Matheson, chief executive officer of the NRECA voiced concern about technologies that had not yet 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.[301]

Similar or competitive systems

• OneWeb satellite constellation – a satellite constellation project that began operational deployment of satellites in 2020.[302]
• China national satellite internet project – a planned satellite internet offering for the Chinese market.[303]
• 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

• AST SpaceMobile – a satellite-to-mobile-phone satellite constellation working with large mobile network operators such as Vodafone, AT&T, Orange, Rakuten, Telestra, Telefonica, etc. with the objective to provide broadband internet coverage to existing unmodified mobile phones
• 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, covering most of the world's landmass
• Iridium – an operational constellation of 66 cross-linked satellites in a polar orbit, used to provide satellite phone and low-speed data services over the entire surface of Earth
• 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

References

External links

• Official website
• Official Starlink Availability Map
• Starlink Satellite and Groundstation Locations, Data Links, path projection, environmental Information etc. (starlink.sx)
• Starlink Coverage Area, Satellite and Groundstation Locations for Starlink, OneWeb and GPS constellations (satellitemap.space)
• Complete Starlink Satellite Catalog allowing tracking location details from user location.
• Starlink Satellite Locations and Information on individual coverage area, connections, etc.
• See A Satellite Tonight shows when Starlink satellites can be seen.
• Shows real-time Starlink satellites position
• Starlink Professional Installers Directory
• List of Starlink dish firmware updates
• A User Friendly Real-Time SpaceX Satellite Locator

На других языках

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- [en] Starlink

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[es] Starlink

Starlink es una empresa que nació como proyecto de SpaceX para la creación de una constelación de satélites de internet[2] con el objetivo de brindar un servicio de internet de banda ancha, baja latencia y cobertura mundial a bajo coste.[3][4] SpaceX comenzó a lanzar satélites Starlink en 2019. En mayo de 2022, Starlink consta de más de 2400 pequeños satélites fabricados en serie en órbita terrestre baja (LEO),[5] que se comunican con los transceptores terrestres designados. En 2017 se completaron los requisitos regulatorios para lanzar cerca de 12.000 satélites para mediados de la década de 2020.[6] SpaceX también planea vender satélites para uso militar,[7] científico y de exploración.[8] En noviembre de 2018, la empresa recibió la autorización del ente gubernamental estadounidense (FCC) para desplegar 7.518 satélites de banda ancha, que se sumarían a los 4.425 aprobados en marzo del mismo año.[9]

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[ru] Starlink

Starlink[1] — глобальная спутниковая система, разворачиваемая компанией SpaceX для обеспечения высокоскоростным широкополосным спутниковым доступом в Интернет в местах, где он был ненадёжным, дорогим или полностью недоступным[2][3]. Подразделение SpaceX, занимающееся исследованиями, разработкой и производством спутниковых систем, расположено в Редмонде (штат Вашингтон).

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