Starlink is a satellite internet constellation program operated by SpaceX providing satellite Internet access to most of the Earth. The constellation consists of over 1600 satellites in mid-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 November 2021, the beta service offering is available in 20 countries.
The deployment of the first 1,440 satellites will be into 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 450 km (280 mi) orbit and expected up to six launches in 2019 at that time, with 720 satellites (12 × 60) for continuous coverage in 2020. In February 2021, Musk stated that the satellites are traveling on 25 orbital planes clustered between 53° north and south of the equator.
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) and SpaceX decided to place the satellites at a relatively low 550 km (340 mi), due to concerns about the space environment. Initial plans as of January 2015 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 system will not directly connect from its satellites to handsets (unlike the constellations from Iridium, Globalstar, Thuraya and Inmarsat). Instead, it will be 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 began to be 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".
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