The Starlink project from American company SpaceX :
Starlink :
Starlink is a company owned by SpaceX that offers satellite Internet access. It relies on a constellation of satellites that includes thousands of communications satellites that are placed in a low-earth orbit. Starlink is the first satellite internet provider to select this orbit over geostationary orbit because it reduces latency (response time) by reducing it from 600 milliseconds to about 20 milliseconds. The constellation has been deploying since 2019 and will have over 3 200 operational satellites by February 2023. At this time, Starlink has about a million customers in fifty-six countries, including France, who have given the company permission to use the system-required frequencies.
SpaceX expects to have 12,000 satellites by 2025, with a total of 42,000 satellites required by the end of the project. Each satellite has a 20 gigabit per second capacity from a technical standpoint, and it uses the Ku band for connections with user terminals and the Ka band for connections with terrestrial stations. The satellite, which travels in a circular orbit at an altitude of about 550 kilometers, has an approximate mass of less than 300 kilograms and is equipped with an ion propulsion system to help it enter and maintain its orbit as well as reduce it over the course of its lifespan (roughly six years), allowing it to be destroyed by atmospheric re-entry .
The user's terminal is supported by a networked phase-controlled antenna with a mechanical height-orientation device.
The cost of manufacturing and placing satellites in orbit is a key factor in Starlink's economic viability. SpaceX uses its Falcon 9 launchers to deploy its constellation at significantly lower costs because to the launcher's reusability and the satellites' compatibility, which allows for the placement of 50 to 60 of these payloads at each launch. Concurrently, a number of businesses plan to launch analog constellations. OneWeb is the most advanced.
Given that the number of low-earth orbiting satellites will be halved by the presence of just the Starlink satellites (in a configuration targeted at 42,000 spacecraft), the deployment of a constellation of satellites this size poses a number of challenges. The likelihood of satellite collisions will rise to significant levels, rendering current anti-collision devices ineffective. The large terrestrial observatories' astronomical observations are hindered by light pollution as well, in particular the surveys and tracking of celestial objects programs.
The Starlink project from American company SpaceX :
The American company SpaceX's Starlink project calls for the launching of 12 000 and 42 000[1] small satellites to provide high-speed internet access to all areas of the planet, but especially to the least populated areas that lack such access because the installation of a terrestrial network (such as fiber optic or other) cannot be financially viable without a sufficient number of users or due to its isolation from denserly populated areas ,According to a report by the US Congress, despite numerous initiatives that helped to lessen the digital divide, around 14,5 million Americans did not have access to high-speed internet in 2021 (defined as a download speed of 25 megabits per second)[4]. The project Starlink distinguishes itself from current satellite internet offerings that rely on large satellites placed in geostationary orbit by having a shorter latency. The anticipated latency is between 25 and 35 milliseconds compared to the 600 milliseconds of geostationary satellites[2], but Elon Musk believes it may be as low as 20 milliseconds or even lower.
According to SpaceX, the project fills a need created by the expansion of new internet uses like networked video games and video conference calls. However, the project, which would multiply by twenty the number of operational satellites already in low-earth orbit, is opposed in particular by other satellite operators because it might significantly increase the risk of collisions[2]. The technologies used are already being used by projects with the exact same goals as Starlink, such as OneWeb, such as Iridium and Globalstar (satellite telephones), LeoSat (point-to-point communication), and others. This one is based on a much smaller number of satellites (less than 1,000), and its launch date has been set for 2022.
For the first time, SpaceX has announced the Starlink project :
SpaceX makes its initial announcement on the Starlink project in January 2015[7]. 2016 saw the construction of a project-specific building in Redmond, close to Seattle[8]. Initial plans called for the constellation to be deployed by 2020, however technical characteristics changes have caused the schedule to slip[9]. Two satellite prototypes named Tintin A and Tintin B were sent into orbit in February 2018 to carry out the demonstrations required by the FCC, the body in charge of regulating communications in the United States[10]. In March 2018, the FCC grants its approval for the deployment of a third of the constellation, subject to the satisfactory completion of the required tests.
First 1,600-satellite constellation :
The initial concept calls for the deployment of 12,000 satellites[1] between 1100 and 1300 kilometers above the earth. However, competing companies' projects force SpaceX to accelerate its own, and the company says it will launch a first constellation of 1,600 satellites in the fall of 2018 at a lower height (550 kilometers). Additionally, the satellites have been simplified to enable the launch of the first examples in June 2019. The satellite only emits in the Ku band, rather than simultaneously in the Ka and Ku bands. SpaceX must launch 2,200 of these satellites in five years, and they must serve as prototypes for the next spacecraft[12].
Beginning in April 2021, more than 1300 Starlink satellites were launched.